Data display control apparatus for controlling the display of data, a data transmission apparatus for transmitting information which is used to control the display of data, and a data display control information editing apparatus for editing information used to control the display of data

ABSTRACT

A data display control apparatus receives a digital broadcast and compares the present time with a time indicated in a Time_Event_Part provided in navigation information used to control the display of the multimedia data composing a broadcast program. When the indicated time has been reached, the data display control apparatus executes instructions to control the display of the multimedia data.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a data display controlapparatus, a data transmission apparatus, and a data display controlinformation editing apparatus. In particular, the present inventionrelates to a data display control apparatus for controlling the displayof a plurality of sets of multimedia data which are linked to oneanother, a data transmission apparatus for transmitting informationcontrols the display of multimedia data, and to a data display controlinformation editing apparatus for editing information used to controlthe display of multimedia data.

[0003] 2. Description of the Related Art

[0004] Since the development of digital satellite broadcasting in recentyears, there has been a great increase in the number of programs beingprovided on an ever greater number of channels. For digital satellitebroadcasting, large numbers of channels are possible by multiplexing thechannels together into a single frequency band. This multiplexing isperformed using what is called a “transport stream” under MPEG2 (MovingPictures Experts Group2) standard. This technique is described in detailin the documentation for ISO/IEC Standard 13818-1 (MPEG2 systemstandard).

[0005] Here, it is possible to conceive a digital broadcasting systemwhere image information and the like are transmitted from a transmissionstation and received by a receiver terminals, with users of the receiverterminals making interactive operations for the image information inaccordance with the content of the transmitted image information.

[0006] The above kind of digital broadcasting system is disclosed by aconcurrent patent application with the title “Digital BroadcastingSystem, Digital Broadcasting Apparatus, and Receiver Apparatus for aDigital Broadcast” (Japanese Patent Application No. H9-62216). Thecharacteristic feature of this digital broadcasting system is that itprovides a variety of interactive services using only a one-way transferof data. The system is described in more detail below.

[0007] The construction of the digital broadcasting system which ispresupposed for the present invention is shown in FIG. 1. This digitalbroadcasting system is composed of a data transmission apparatus 101 anda plurality of data reception apparatuses 121.

Data Transmission Apparatus 101

[0008] The data transmission apparatus 101 is constructed to multiplexdata for a plurality of contents, which feature hyperlinks to oneanother, into an MPEG2 transport stream and to repeatedly transmit themultiplexed data. This data transmission apparatus 101 is composed of atransmission data storage unit 102, a data multiplexing unit 103, amultiplexing information storage unit 104, a system information tablegenerating unit 105, and a transmission unit 106. Here, the term“content” is used to express the unit of information for whichinteractive operations can be performed by the user.

[0009] The transmission data storage unit 102 is composed of a recordingmedium such as a magnetic disc, and stores data for a plurality ofcontents which compose one interactive program, and constructioninformation. This transmission data storage unit 102 includes apresentation information storage unit 107, a navigation informationstorage unit 108, and a construction information storage unit 109. Here,an “interactive program” refers to an “event” or “program” which isincluded in the MPEG2 transport stream used as the transmission data.

[0010] The presentation information storage unit 107 stores presentationinformation, such as image data and audio data, which is included ineach content. The navigation information storage unit 108 stores thenavigation information which is composed of hyperlink information forlinks to other contents, operation control information such as scriptsfor switching the display, and supplementary display images fordisplaying menus and the like on a display screen. The constructioninformation storage unit 109, meanwhile, stores a constructioninformation table which shows the correspondence between sets of imagedata and navigation information.

[0011] The multiplexing information storage unit 104 stores amultiplexing information table including identifiers and assigninginformation for resources such as bandwidth for is multiplexing thetransmission data stored in the transmission data storage unit 102 intoan MPEG2 transport stream.

[0012] This multiplexing information table includes packet identifiers(PID) which are assigned to the components that compose each event, whenthe data stored in the transmission data storage unit 102 is multiplexedinto the MPEG2 transport stream as an event.

[0013] The components referred to here are streams which are eachidentified by a PID under IS/IEC 13818-1 (hereinafter, MPEG2 system)standard, with there being video components, audio components,components for multiplexing navigation information, and components formultiplexing stream correspondence information (described later in thisspecification).

[0014] The data multiplexing unit 103 is composed of a multiplexingcontrol unit 110 made up of a CPU and memory, a stream correspondenceinformation table generating unit 111, an identifier informationappending unit 112, a navigation information table generating unit 113,and a multiplexing unit 114.

[0015] On being activated by the transmission unit 106, the multiplexingcontrol unit 110 first reads the construction information table and themultiplexing information table stored in the construction informationstorage unit 109 and the multiplexing information storage unit 104, andassigns identifiers for uniquely identifying each content in the digitalbroadcast for each content number, in doing so generating a contentidentifier assigning table. After this, the multiplexing control unit110 assigns values of a “PID”, “component_tag”, and “stream_id” to eachset of image data and generates a display image information identifierassigning table. The multiplexing control unit 110 also instructs thestream correspondence information table generating unit 111 to generatea stream correspondence table, instructs the identifier informationappending unit 112 to add the identifier VE_id for image data (videoelement “VE”) to the private area of the image data, and instructs thenavigation information table generating unit 113 to generate thenavigation information table for the navigation elements “NE”.

[0016] On being instructed by the multiplexing control unit 110 to addthe identifier information, the identifier information appending unit112 reads the image data stored in the presentation information storageunit 107. The identifier information appending unit 112 then writes theimage data identifier VE_id into the private area of the image data bitstream it has read. It should be noted here that the identifierinformation appending unit 112 obtains the VE_id by referring to thedisplay image information identifier assigning table generated by themultiplexing control unit 110. The identifier information appending unit112 then assigns a filename to the image data bitstream with the addedVE_id information and stores it in a storage area (not illustrated).After appending identifier information to all of the image data, theidentifier information appending unit 112 informs the multiplexingcontrol unit 110 of the completion of the appending operation.

[0017] On being instructed by the multiplexing control unit 110 togenerate a navigation information table, the navigation informationtable generating unit 113 reads the navigation information stored in thenavigation information storage unit 108. When the read navigationinformation includes hyperlink information, the navigation informationtable generating unit 113 refers to the content identifier assigningtable for information regarding the link destination given as a contentnumber and converts this content number into a variety of identifiers togenerate a navigation information table. When no hyperlink informationis included, the navigation information table generating unit 113generates the navigation information table by using the read navigationinformation as it is, changing only the filename. The navigationinformation table generating unit 113 stores the generated navigationinformation table in a storage area (not illustrated). Hereinafter, theexpression “navigation information” will mainly refer to the navigationinformation tables generated here.

[0018] On completing the generation of the navigation informationtables, the navigation information table generating unit 113 informs themultiplexing control unit 110 of the completion of its processing.

[0019] On being instructed by the multiplexing control unit 110 togenerate a stream correspondence table, the stream correspondenceinformation table generating unit 111 refers to the display imageinformation identifier assigning table and generates a streamcorrespondence table for each set of image data. These streamcorrespondence tables are used by data reception apparatuses to separateone set of image data from the stream transmitted from the datatransmission apparatus 101 to the data reception apparatus 121.Hereinafter, the expression “stream correspondence information” willmainly refer to the stream correspondence tables generated here.

[0020] On completing the generation of the stream correspondence tables,the stream correspondence information table generating unit 111 informsthe multiplexing control unit 110 of the completion of its processing.

[0021] On receiving indications for the completion of processing by theidentifier information appending unit 112, the navigation informationtable generating unit 113, and the stream correspondence informationtable generating unit 111, the multiplexing control unit 110 decides thenumber of contents which are to be repeatedly transmitted.

[0022] The multiplexing unit 114 multiplexes the transmission data intoan MPEG2 transport stream.

[0023] The system information table generating unit 105 refers to themultiplexing information storage unit 104 and generates the NIT (NetworkInformation Table), the EIT (Event Information Table), the SDT (ServiceDescription Table), the PAT (Program Association Table), and the PMT(Program Map Table). These tables compose the program specificationinformation which is used by the data reception apparatus 121 inselecting a program. Hereinafter, the tables, such as the NIT and EIT,generated by the system information table generating unit 105 will begenerally referred to as the “system information”.

[0024] On being instructed by the multiplexing control unit 110, thesystem information table generating unit 105 refers to the multiplexinginformation storage unit 104 and generates the NIT, the EIT, the SDT,and the PAT in accordance with DVB-SI standard and MPEG2 systemstandard. These tables include information which is required by the datareception apparatus 121 to select the events which are composed of thedata stored in the transmission data storage unit 102.

[0025] The NIT stores information which relates to the transfer path foreach transport stream transmitted from a network identified as thespecified network. The EIT stores information, such as event names,starting times, and ending times, for each of the events in a specifiedservice. The SDT stores information, such as service names, for eachservice included in a specified transport stream.

[0026] The PAT includes information for the PIDs of the PMT (Program MapTable) for each program included in a specified transport stream.

[0027] The system information table generating unit 105 also refers tothe multiplexing information table and generates the PMT. The PMTincludes PIDs for identifying each component which composes a program,the types of data transmitted in each component, and information for thedescriptors which correspond to each component.

[0028] The transmission unit 106 includes a scheduler, and activates themultiplexing control unit 110 at a predetermined time before thetransmission start time of an event, such as five minutes beforetransmission. When the transmission start time is reached, thetransmission unit 106 repeatedly multiplexes information such as theNIT, PAT, PMT, SDT, and EIT generated by the system information tablegenerating unit 105 into the transport stream outputted by themultiplexing unit 114 at a predetermined interval using predeterminedPIDs in accordance with DVB-SI standard and MPEG2 system standard. Thetransmission unit 106 then performs modulation and other processes,before transmitting the data to a plurality of data receptionapparatuses 121.

[0029] As described above, the data transmission apparatus 101 assignsidentifiers to the image data and navigation information table whichcompose each content, multiplexes them into a transport stream, andrepeatedly performs transmission.

[0030] The navigation information includes identifiers of a set of imagedata and a set of navigation information in the content linked by ahyperlink, as well as supplementary image information for displayingmenus and the like, and scripts for switching the display. As a result,the data reception apparatus 121 can freely separate and reproduce acontent from the transport stream by specifying the identifiers inaccordance with the navigation information, which means that interactiveoperations can be performed for data transmitted using a one-waycommunication path.

Data Reception Apparatus

[0031] The data reception apparatus 121 is constructed to selectivelyobtain and reproduce a content from the MPEG2 transport streamtransmitted by the data transmission apparatus 101, in accordance withan interactive operation made by the user. This data reception apparatus121 is composed of a reception unit 122, a TS decoder unit 123, an AVdecoder unit 124, a received data storage unit 125, a reception controlunit 126, a signal reception unit 127, a reproduction unit 128, adisplay unit 129, and an audio output unit 130.

[0032] The reception unit 122 receives the MPEG2 transport stream whichcorresponds to the transport stream identifier indicated by thereception control unit 126, and outputs it to the TS decoder unit 123.

[0033] The TS decoder unit (transport decoder unit) 123 includes afilter condition storage unit 131 for storing the filter conditions setby the reception control unit 126, and operates in accordance with thesefilter conditions so as to only separate image data or audio data with aspecified identifier from the transport stream outputted by thereception unit 122. The TS decoder unit 123 outputs the separated datato the AV decoder unit 124. The TS decoder unit 123 also separatesstream correspondence tables, navigation information tables, and systeminformation tables which have been multiplexed as table data under MPEG2standard, and outputs the table data to areas maintained in the receiveddata storage unit 125, in accordance with the identifiers.

[0034] The TS decoder unit 123 also separates the PCR (Program ClockReference) with the specified identifier and outputs it to the AVdecoder unit 124. It should be noted here that the filter conditionstorage unit 131 can simultaneously store a plurality of filterconditions and that the TS decoder unit 123 can simultaneously perform aplurality of separation operations in parallel.

[0035] The AV decoder unit 124 includes a clock unit which is notillustrated. This clock unit is synchronized to a standard time usingthe value of the PCR outputted by the TS decoder unit 123, and is usedto measure time which is used as the standard for synchronized decodingof image data and audio data.

[0036] On receiving image data and/or audio data from the TS decoderunit 123, the AV decoder unit 124 reads the identifier of the image dataand/or audio data written in the private area, in accordance with anindication from the reception control unit 126, and notifies thereception control unit 126 of the identifier(s). Next, the AV decoderunit 124 decodes the image data and/or audio data in predetermined unitsin accordance with an indication from the reception control unit 126 andoutputs the decoded data to the reproduction unit 128 in synchronizationwith the clock unit, before informing the reception control unit 126 ofthe completion of the decoding.

[0037] The received data storage unit 125 can be composed of RAM (RandomAccess Memory), for example, and is provided with a streamcorrespondence information table storage unit 132, a navigationinformation table storage unit 133, and a system information tablestorage unit 134.

[0038] The stream correspondence information table storage unit 132stores stream correspondence tables which have been separated by the TSdecoder unit 123. The navigation information table storage unit 133stores navigation information tables which have been separated by the TSdecoder unit 123. The system information table storage unit 134 storesthe system information tables, such as the NIT, the SDT, the EIT, thePAT, and the PMT, which have been separated by the TS decoder unit 123.

[0039] The signal reception unit 127 receives signals, such as remotecontroller operations made by a user, and informs the reception controlunit 126 of the received signals.

[0040] The reproduction unit 128 superimposes graphics informationincluded in the navigation information table outputted from thereception control unit 126 and image data decoded by the AV decoder unit124 in accordance with indications from the reception control unit 126.The reproduction unit 128 outputs this combined image to the displayunit 129. The reproduction unit 128 also outputs audio data decoded bythe AV decoder unit 124 to the audio output unit 130.

[0041] The display unit 129 can be realized by a CRT (Cathode Ray Tube)or liquid crystal display, and is used to display the images outputtedby the reproduction unit 128.

[0042] The audio output unit 130 can be realized by a speaker, and isused to output the audio signal outputted by the reproduction unit 128.

[0043] The reception control unit 126 is composed of a CPU and a programfor controlling the CPU. The reception control unit 126 controls thereception unit 122 and has it receive a desired transport stream. Onreceiving a user operation signal via the signal reception unit 127, thereception control unit 126 refers to the navigation information tablepresently stored in the navigation information table storage unit 133and sets the filter condition for the next navigation information tableand the filter condition for the stream correspondence table forobtaining the image data in the filter condition storage unit 131 of theTS decoder unit 123. The reception control unit 126 then refers to thestream correspondence table which has been newly separated by the TSdecoder unit 123 and stored in the stream correspondence informationtable storage unit 132, and sets the filter condition for the image datain the filter condition storage unit 131.

[0044] The reception control unit 126 judges whether the image datawhich has been separated by the reception control unit 126 is theappropriate image data by referring to the image data identifier writteninto the private area of the image data. When the image data is theappropriate image data, the reception control unit 126 has the imagedata decoded and outputted to the reproduction unit 128. When the imagedata is not the appropriate image data, the reception control unit 126changes the filter condition in the filter condition storage unit 131and gives another indication for the separation of a streamcorrespondence table.

[0045] The reception control unit 126 also reads graphics data forobjects included in the supplementary image information in thenavigation information table separated by the TS decoder unit 123. Thereception control unit 126 also informs the reproduction unit 128 ofthis data and has the reproduction unit 128 combine the bitmap data withthe image data.

[0046] As described above, the data reception apparatus 121 can separatethe presentation information and navigation information for a specifiedcontent from the transport stream when necessary. By doing so, suitablelink destination contents can be reproduced in accordance with useroperations, so that interactive programs that can be changed inaccordance with user operations can be achieved despite thecommunication being limited to a one-way broadcast from the datatransmission apparatus.

Operation

[0047] The following is an explanation of the data composition ofcontents and of the operation for the display of contents by the datareception apparatus 121 in this digital broadcasting system, withreference to the drawings.

[0048]FIG. 2 shows an example display which is displayed by the datareception apparatus 121 in the digital broadcasting system describedabove. This figure shows an example of a mail order program, with therebeing a content 210 showing a mail order menu, a content 220 introducingvideo equipment, and a content 230 introducing stereo equipment. Here,switching between these contents can be performed according to useroperations, as shown by the arrows 240, 241, 242, and 243.

[0049] When the content 210 showing the mail order menu is displayed onthe display screen and the user selects and activates the “video” button211, the display switches, as shown by arrow 240, from content 210 to adisplay of content 220 that introduces video equipment. Following this,if the user selects and activates the “Menu” button 221, the displayswitches back to the content 210 showing the mail order menu, as shownby the arrow 241.

[0050] In the same way, when the content 210 showing the mail order menuis displayed on the display screen and the user selects and activatesthe “Stereo” button 212, the display switches, as shown by arrow 243,from content 210 to a display of content 230. Following this, if theuser selects and activates the “Menu” button 231, the display switchesback to the content 210 showing the mail order menu, as shown by thearrow 242. Here, buttons 211, 212, 221, and 231 are provided in contents210, 220, and 230 to allow switches of display in accordance with theinteractive operations made by the user.

[0051] To achieve the switches of display in response to interactiveoperations described above, the data which composes each of the contentstransmitted by the data transmission apparatus 101 needs to have theconstruction described below.

[0052]FIG. 3 is a simplified representation of the data transmitted bythe data transmission apparatus. Here, the transmitted data 201 iscomposed of data representing the various contents, and is repeatedlytransmitted in its entirety, with each repeated transmission having apredetermined time period. This data is repeatedly transmitted to allowthe data corresponding to a content selected by an indication of a linkdestination given by the user to be obtained at any given time. Sincethe data for the contents is repeatedly transmitted, the user will soonbe able to obtain the data for the required content even when the userhas commenced viewing midway through the broadcast of the program.

[0053] The transmitted data 201 is composed of a plurality of sets ofimage data 215, 225, and 235, and a plurality of sets of navigationinformation 216, 226, and 236 which correspond to the sets of imagedata. These sets of image data 215, 225, and 235 correspond to thebackground images of contents 210, 220, and 230 which are displayed onthe display screen of the data reception apparatus 121.

[0054] The sets of navigation information 216, 226, and 236 includebitmap data for on-screen display graphics, such as buttons, which aredisplayed superimposed onto the sets of image data 215, 225, and 235,scripts which describe operation processes corresponding to useroperations, and hyperlinks showing contents that are link destinationsfor display switching of contents. This hyperlink information iscomposed of identifiers for the data, such as image data, and thenavigation information which compose the link destination contents.

[0055] The content 210 shown in FIG. 2 is achieved by the image data 215and the navigation information 216. In the same way, content 220 shownin FIG. 2 is achieved by the image data 225 and the navigationinformation 226, and content 230 shown in FIG. 2 is achieved by theimage data 235 and the navigation information 236.

[0056]FIG. 4 is a model representation of the repeated transmission ofdata 201 with the given interval. This data 201 is repeatedlytransmitted with the given interval by the data transmission apparatus101.

[0057] It should be noted that while the image data and navigationinformation in FIG. 4 have been illustrated with a frame construction,the respective data is in fact digitized, with image data andcorresponding navigation information being multiplexed together and thedata 201 being transmitted as an MPEG2 transport stream.

[0058] The following is a detailed explanation of the data multiplexedand transmitted by the data transmission apparatus 101.

[0059]FIG. 5 shows how the data transmitted by the data transmissionapparatus 101 is multiplexed together. As shown in the figure, imagedata VE(N), navigation information tables NE(N), stream correspondencetables VET(N), and system information such as the PCR, PAT, and PMT aremultiplexed together. The arrow 202 in FIG. 5 shows the range of thedata 201 in FIG. 4 which is repeatedly transmitted.

[0060] In the example shown in FIG. 5, sixty-three contents aremultiplexed together, with the sets of image data VE(0) to VE(62) eachbeing multiplexed with the value “0×0084” as their PID and a value whichis cyclically incremented between “0×e0” and “0×ef” as their stream_id.Each set of stream correspondence information VET(N) is multiplexed withthe value “0×0083” as their PID and a value equal to the image dataidentifier VE_id as their table_id_extension. Here, one set of streamcorrespondence information VET(N) is multiplexed for each set of imagedata VE(N). The sixty-three sets of navigation information NE(0) toNE(62) are multiplexed having been given the value “0×0082” as their PIDand a value equal to the navigation element identifier NE_id as theirtable_id_extension. Here, the PCR, PAT, and PMT are also multiplexedwith predetermined values of the PID.

[0061] Here, the table_id_extension and stream_id are identifiers whichare used in conjunction with the PID to identify the various sets ofdata.

[0062] With the stated data construction, the data reception apparatus121 can set these identifiers into the filter condition storage unit 131as indicated by the received data, so that the TS decoder unit 123 canseparate the desired data from the transmitted transport stream.

[0063] Since the VE_id identifier of the image data and the NE_ididentifier of the navigation information are given in the hyperlinkinformation in the navigation information corresponding to the contentpresently being displayed to enable the execution of hyperlinks inaccordance with user operations, it is possible to separate the datacomposing the next content to be displayed based on the hyperlinkinformation and so display the next content. This procedure is describedin more detail below.

[0064] First, the data reception apparatus 121 obtains the PAT of thetransponder (satellite broadcasting unit) presently being received.Here, when the program selected by the user is on a differenttransponder, the data reception apparatus 121 obtains the NIT, refers tothe NIT, and controls the reception unit 122 to change the receivedtransponder, although such case will not be described here.

[0065] Since the PID of the PAT is set beforehand at “0”, the datareception apparatus 121 sets “PID=0” into the filter condition storageunit 131 so as to separate the PAT. Since the PID of the PMT is given inthe PAT, the data reception apparatus 121 can obtain the PID of the PMTcorresponding to the program and, by setting this into the filtercondition storage unit 131, separate the PMT.

[0066] The PIDs corresponding to the components are given in the PMT, sothat the data reception apparatus 121 can obtain the PID of the streamcorrespondence table VET, and, by setting the VE_id obtained from thehyperlink information together with the table_id_extension into thefilter condition storage unit 131, the stream correspondence table VETcorresponding to the desired image data can be obtained.

[0067] The component_tag and stream_id are given in the streamcorrespondence table VET, so that the data reception apparatus 121 canrefer to the PMT based on the component_tag and obtain the PID of theappropriate component. By setting this PID and the stream_id in thefilter condition storage unit 131, the data reception apparatus 121 canobtain and display the desired image data.

[0068] The data reception apparatus 121 is also able to obtain the PIDof the component used for multiplexing the navigation information byreferring to the PMT, and by setting the NE_id obtained from thehyperlink information with the table_id_extension in the filtercondition storage unit 131, can separate the desired navigationinformation.

[0069] As a result of the described procedure, the data receptionapparatus 121 can obtain the image data and navigation information whichcompose the new content.

[0070] The following is a more detailed explanation of the dataconstruction of the navigation information, using the example of thenavigation information 216 which is given in outline in FIG. 3. The dataconstruction of this navigation information 216 is shown in FIG. 6.

[0071] The navigation information 216 includes a Bytecode_Part 301, aHandler_Part 302, a Graphics_Property_Part 303, aBitmap_Information_Part 304, and a Hyperlink_Information_Part 305.

[0072] The Bytecode_Part 301 is equivalent to the part of FIG. 3represented by the word “Script”, and is used to record bytecodes whichare one kind of script. These bytecodes include an instruction set, suchas conditional branches, integer calculations, and access toconstants/variables, which allows basic programming, and to a variety ofinstruction sets that are related to the control of image and audiodata.

[0073] In the example in FIG. 6, the bytecode with bytecode number “0”is “Push L0, GotoPage”. Here, “Push L0” is an instruction whichrepresents the storing of the value “0” in the stack, while “GotoPage”is an instruction indicating a switch of display to the content shown bythe link number whose value is stored in the stack. Here, the linknumber is given in the Hyperlink_Information_Part 305, and is anidentifier for identifying a content to be switched to. Accordingly, thebytecode with the bytecode number “0” describes an operation switchingthe display to the link destination content given by link number “0”. Inthe same way, the bytecode with the bytecode number “1” describes anoperation switching the display to the link destination content given bylink number “1”.

[0074] The Handler_Part 302 is used to record the correspondence betweenhandler numbers and bytecode numbers. In the example in FIG. 6, thehandler numbers 0 and 1 respectively correspond to the bytecode numbers0 and 1. It should be noted here that not only bytecodes, but alsoinformation defining the processing environment of handlers, such asvariable areas, is given corresponding to the handlers.

[0075] The Bitmap_Information_Part 304 is the part used to record thecontent of the bitmaps which display buttons corresponding to thegraphics numbers. In the example in FIG. 6, the graphics with the number“0” represent the bitmap “Video”, while the graphics with the number “1”represent the bitmap “Stereo”.

[0076] The Graphics_Property_Part 303 is information for composing theon-screen display graphics to be displayed superimposed onto the videodata on the display screen, and so includes graphics numbers foridentifying sets of graphics, graphics types, display coordinates forsets of graphics, a handler number associated with the graphics, and anentry showing the initial state for when the content is displayed. Forthe example in FIG. 6, the type for each set of graphics is “button”,with graphics numbers 0 and 1 corresponding to the graphics in theBitmap_Information_Part 304 with the same values “0” and “1”.Hereinafter, the button with the graphics number “n” will be referred toas “button n” or the “nth button”. In the present example, button 0 andbutton 1 are displayed with the x and y coordinates given as (20,20) and(20,60), with the handler numbers of the handlers which are activated onselection of the buttons 0 and 1 being “0” and “1”. Also, the initialstate of button 0 and button 1 when the content is displayed is“visible”.

[0077] The Hyperlink_Information_Part 305 is used to record the IDs ofthe materials which compose the link destination contents. ThisHyperlink_Information_Part 305 records the IDs as the informationshowing all of the link destination contents of the content whichincludes this navigation information. Here, link numbers are given toidentify the sets of identifiers for the link destinations of eachcontent. For the example in FIG. 6, NE_id=1, VE_id=1 are recorded forthe link destination with the link number “0”, with this indicating alink destination content composed of the information in the NE with theID number “1” and the VE with the ID number “1”. The NE_id=2, VE_id=2are recorded for the link destination with the link number “1”, withthis indicating a link destination content composed of the informationin the NE with the ID number “2” and the VE with the ID number “2”.

[0078] It should be noted here that NE_id given as “0” at the top ofFIG. 6 shows that the navigation information being explained here is thenavigation element which has the ID “0”.

[0079] In the data reception apparatus 121, the reception control unit126 refers to the navigation information composed of the data describedabove and displays the button “Video” and the button “Stereo” shown incontent 210 of FIG. 2. When these buttons are selected and activated bythe user, control is performed to switch the display to another content.

[0080] When a content is displayed, the reception control unit 126refers to the Graphics_Property_Part and displays the graphics in orderstarting from the graphics with the graphics number “0” in the indicatedinitial state at the indicated coordinates. When a button is selectedand activated by the user, the reception control unit 126 executes thehandler process corresponding to the handler number given in theGraphics_Property_Part. This handler processing is performed by thereception control unit 126 referring to the Handler_Part and executingthe bytecode in the Bytecode_Part which has the bytecode number givencorresponding to the handler number in the Handler_Part. It should benoted that this execution of bytecodes is achieved by a bytecodeinterpreter (not illustrated) in the reception control unit 126separating and executing one instruction at a time.

[0081] In the digital broadcasting system described above, the data,such as the image data and navigation information, necessary fordisplaying each content is repeatedly multiplexed and transmitted by thedata transmission apparatus. The data reception apparatus which receivesthis data is able to separate data from the transmitted data inaccordance with selection and activation operations made by the user, sothat a desired content can be displayed. By doing so, an interactiveservice can be achieved using a one-directional broadcast.

[0082] In current broadcasting, there are cases where a broadcast of asame program is repeated several days later, and to reduce productioncost and effort, there are demands for the data used to compose aprogram to be used once again in exactly the same form.

[0083] When considering the above demands, a broadcast which includesimage data with a content such as “Campaign valid until Sep. 10, 1996”may be broadcast as it is until Sep. 10, 1996. When Sep. 11, 1996 isreached, however, it becomes unsuitable to broadcast the data as it is.In this way, there can be cases where a program will contain data whichis not suitable for a repeat broadcast, so that it is necessary todevelop a system where control is perform in accordance with the time ofbroadcast to prevent links to data unsuitable for repeat broadcastingbeing activated.

[0084] It is also common in the world of broadcasting for a variety ofdifferent programs to be broadcast at different times, so that there aredemands for the dynamic setting of links between programs with differentbroadcasting times so as to link the various programs. In order tosatisfy these demands, it is necessary to have a construction whichperforms control in accordance with the ending times of programs whichare link destinations.

[0085] In the above digital broadcasting system, it is necessary to havea control structure for programs which include a time element. By doingso, program producers can efficiently generate and broadcast a greatvariety of programs, with the viewers being able to enjoy a widervariety of interactive programs.

[0086] In order to satisfy the need for the above kind of programservice, it is necessary to perform program control with a time elementfor the system described here as the related art.

SUMMARY OF THE INVENTION

[0087] To satisfy the need for the kind of service described abovewithin the framework of the related art, it is a first object of thepresent invention to provide a data display control apparatus that has acontrol mechanism for programs that include a time element. This datadisplay control apparatus is an apparatus that can receive datatransmitted by a data transmission apparatus and can display data inaccordance with user operations.

[0088] It is a second object of the present invention to provide a datatransmission apparatus that can transmit data that enables therealization of a control mechanism for programs that include a timeelement.

[0089] It is a third object of the present invention to provide a datadisplay control information editing apparatus that edits controlinformation for realizing a control mechanism for programs that includea time element.

[0090] The first object of the present invention can be achieved by adata display control apparatus for receiving a plurality of sets ofmultimedia data and a set of time control information, and forcontrolling the display of the sets of multimedia data, the plurality ofsets of multimedia data composing a plurality of contents which make upa broadcast program, and the set of time control information being usedfor controlling a display of the sets of multimedia data, the datadisplay control apparatus including: a data storage unit; a receivingunit for extracting at least one set of multimedia data and the set oftime control information from data transmitted from a broadcast programtransmission apparatus and storing the received sets of multimedia dataand the set of time control information into the data storage unit; acurrent time information obtaining unit for obtaining a set of currenttime information including an expression of a current time; a timeinformation judging unit for judging whether control relating to adisplay of the sets of multimedia data is possible by comparing the setof current time information with the set of time control information;and a display control unit for controlling the display of the sets ofmultimedia data based on a judging result of the time informationjudging unit.

[0091] With the stated construction, it is possible to realize a datadisplay control apparatus where the time information used for control iscompared with the current time to see whether control should beperformed for the display of multimedia data, so that display of datacan be executed where time as a condition.

[0092] Here, the set of time control information may be repeatedlytransmitted by the broadcast program transmission apparatus.

[0093] With the stated construction, it is possible to realize a datadisplay control apparatus that is able to soon obtain the timeinformation used for controlling a content, when, at an arbitrary time,the user tries to have a content displayed by making an operationindicating a link destination.

[0094] Here, the data display control apparatus may also include: a linkinstruction receiving unit for receiving an instruction input by a userwhich specifies a new content to be displayed; and a link instructionexecuting unit for displaying the new content according to theinstruction received by the link instruction receiving unit.

[0095] With the stated construction, it is possible to realize a datadisplay control apparatus that enables the user to perform interactiveoperations for the display of contents.

[0096] Here, the receiving unit may also extract the set of current timeinformation from the data transmitted from the broadcast programtransmission apparatus, and the current time information obtaining unitmay obtain the current time information from the receiving unit.

[0097] With the stated construction, since the time information isobtained by extracting it from the transmitted data, the timing at whichoperations are made for the display of multimedia data will be the sameas the timing intended by the producer of the program.

[0098] Here, the data storage unit may store a time difference valuewhich indicates a time difference between the expression of the currenttime in the set of current time information and a standard control timein the set of time control information, and the control judging unit mayrefer to the time difference value and correct a content of the currenttime information using the time difference when comparing the set ofcurrent time information with the set of time control information.

[0099] With the stated construction, it is possible to realize a datadisplay control apparatus that can execute operations for the display ofmultimedia data at almost the same timing as intended by the producer ofthe program, even when there is a time difference between the currenttime and the time in the time control information for controlling thedisplay of multimedia data.

[0100] Here, the receiving unit may extract the time difference valueand the set of current time information from the data transmitted fromthe broadcast program transmission apparatus and storing the extractedtime difference value in the data storage unit, and the current timeinformation obtaining unit may obtain the set of the current timeinformation from the receiving unit.

[0101] With the stated construction, it is possible to realize a datadisplay control apparatus that can execute operations for the display ofmultimedia data at exactly the same timing as intended by the producerof the program, even when there is the time difference described above.

[0102] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data thatcompose a plurality of contents which make up a broadcast program, andfor controlling a display of the sets of multimedia data, the datadisplay control apparatus including: a data storage unit; a receivingunit for extracting, from data transmitted from a broadcast programtransmission apparatus, the plurality of sets of multimedia data, atleast one instruction for executing a certain operation, and at leastone set of time control information for controlling execution of atleast one related instruction, the receiving unit storing the separatedsets of multimedia data, instructions, and sets of time controlinformation into the data storage unit; a current time informationobtaining unit for obtaining a set of current time information includingan expression of a current time; a time information judging unit forjudging whether execution of an arbitrary instruction is possible bycomparing the set of current time information with a set of time controlinformation related to the arbitrary instruction; a display control unitfor executing the arbitrary instruction based on a judging result of thetime information judging unit; a link instruction receiving unit forreceiving an instruction input by a user which specifies a content to bedisplayed; and a link instruction executing unit for displaying thecontent according to the instruction received by the link instructionreceiving unit.

[0103] With the stated construction, it is possible to realize a datadisplay control apparatus that can control whether instructions denotingoperations should be executed based on an indicated time.

[0104] Here, the instructions may be instructions that control a displayof the sets of multimedia data.

[0105] With the stated construction, it is possible to realize a datadisplay control apparatus that can control the execution for operationsrelating to the display of multimedia data based on time.

[0106] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data and aplurality of sets of time control information, and for controlling thedisplay of the sets of multimedia data, the plurality of sets ofmultimedia data composing a plurality of contents which are elements ofa broadcast program, each of the plurality of sets of time controlinformation being related to a set of multimedia data and being used forcontrolling a display of the related set of multimedia data, the datadisplay control apparatus including: a data storage unit; a receivingunit for extracting at least one set of multimedia data and at least oneset of time control information from data transmitted from a broadcastprogram transmission apparatus and for storing the sets of multimediadata and the sets of time control information into the data storageunit; a current time information obtaining unit for obtaining a set ofcurrent time information including an expression of a current time; atime information judging unit for judging whether control relating to adisplay of an arbitrary set of multimedia data is possible by comparingthe set of current time information with a set of time controlinformation related to the arbitrary set of multimedia data; a displaycontrol unit for controlling the display of the arbitrary set ofmultimedia data based on a judging result of the time informationjudging unit; a link instruction receiving unit for receiving aninstruction input by a user which specifies a content to be displayed;and a link instruction executing unit for displaying the contentaccording to the instruction received by the link instruction receivingunit.

[0107] With the stated construction, it is possible to realize a datadisplay control apparatus that can control display of units ofmultimedia data based on time.

[0108] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data and aplurality of sets of time control information and controlling display ofthe sets of multimedia data, wherein the plurality of sets of multimediadata compose a plurality of contents which make up a broadcast program,and each set of time control information corresponds one of theplurality of contents, the data display control apparatus including: adata storage unit; a receiving unit for extracting at least one set ofmultimedia data and at least one set of time control information fromdata transmitted from a broadcast program transmission apparatus andstoring the sets of multimedia data and the sets of time controlinformation into the data storage unit; a current time informationobtaining unit for obtaining a set of current time information includingan expression of a current time; a link instruction receiving unit forreceiving an instruction input by a user which specifies a content to bedisplayed; a link instruction executing unit for displaying the contentaccording to the instruction received by the link instruction receivingunit; a time information judging unit for judging, when the linkinstruction executing unit displays the content, whether controlrelating to a display of the content is possible by comparing the set ofcurrent time information with a set of time control information relatedto the displayed content; and a display control unit for controlling thedisplay of the content based on a judging result of the time informationjudging unit.

[0109] With the stated construction, it is possible to realize a datadisplay control apparatus that performs control of display for contentunits based on time.

[0110] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data, at leastone instruction, and one set of time control information related to eachinstruction, and for controlling display of the sets of multimedia databy executing the instructions, wherein the plurality of sets ofmultimedia data compose a plurality of contents which make up abroadcast program, and wherein each set of time control information isused for controlling execution of the related instruction, the datadisplay control apparatus including: a data storage unit; a receivingunit for extracting at least one set of multimedia data, at least oneinstruction, and at least one set of time control information from datatransmitted from a broadcast program transmission apparatus and storingthe received sets of multimedia data, the received instructions, andreceived sets of time control information into the data storage unit; acurrent time information obtaining unit for obtaining a set of currenttime information including an expression of a current time; a timeinformation judging unit for judging whether an execution of anarbitrary instruction is possible by comparing the set of current timeinformation with a set of time control information related to thearbitrary instruction; a display control unit for executing thearbitrary instruction based on a judging result of the time informationjudging unit; a link instruction receiving unit for receiving aninstruction input by a user which specifies a content to be displayed;and a link instruction executing unit for displaying the contentaccording to the instruction received by the link instruction receivingunit.

[0111] With the stated construction, it is possible to realize a datadisplay control apparatus that automatically performs display at apredetermined time.

[0112] Here, the sets of time control information may also be related tothe contents, and the display control unit may execute the arbitraryinstruction when a content related to the set of time controlinformation compared by the time information judging unit is beingdisplayed.

[0113] With the stated construction, it is possible to realize a datadisplay control apparatus that executes a specified operation such asthe display of multimedia data only when a specified content ispresently being displayed.

[0114] Here, each set of time control information may indicate anabsolute control time and the set of current time information includesan absolute current time as the expression of a current time, and thetime information judging unit may judge that execution of the arbitraryinstruction is possible when the control time is equal to or earlierthan the absolute current time.

[0115] With the stated construction, it is possible to realize a datadisplay control apparatus that can perform the display of multimediadata once a predetermined time period has elapsed, but will not displaythe data before this predetermined time period has elapsed.

[0116] Here, each set of time control information may indicate a controlelapsed time and the set of current time information indicates anelapsed time from a start of a display of a current content as theexpression of a current time, and the time information judging unit mayjudge that execution of the arbitrary instruction is possible when theelapsed time is equal to or greater than the control elapsed time in aset of time control information for the arbitrary instruction.

[0117] With the stated construction, it is possible to realize a datadisplay control apparatus that can perform the display of multimediadata once a predetermined time period has elapsed from the start ofdisplay of a content.

[0118] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data, at leastone instruction, and at least one set of time control information, andfor controlling display of the sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, wherein the instructions are used tocontrol a display of the sets of multimedia data, and wherein each setof time control information is used for controlling execution of arelated instruction and is also related to a grouping of sets ofmultimedia data, the data display control apparatus including: a datastorage unit; a receiving unit for extracting, from data transmittedfrom a broadcast program transmission apparatus, at least one set ofmultimedia data, at least one instruction, at least one set of timecontrol information, and a set of identification information for agrouping of sets of multimedia data, and for storing the sets ofmultimedia data, the received instructions, the received set of timecontrol information, and the received set of identification informationinto the data storage unit; a current time information obtaining unitfor obtaining a set of current time information for a current time; atime information judging unit for judging whether execution of anarbitrary instruction is possible by comparing the set of current timeinformation with a set of time control information related to thearbitrary instruction; a display control unit for referring to thereceived set of identification information, and, when a set ofmultimedia data belonging to the grouping of sets of multimedia dataidentified by the set of identification information is being displayed,executing the arbitrary instruction based on a judging result of thetime information judging unit; a link instruction receiving unit forreceiving an instruction input by a user which specifies a content to bedisplayed; and a link instruction executing unit for displaying thecontent according to the instruction received by the link instructionreceiving unit.

[0119] With the stated construction, it is possible to realize a datadisplay control apparatus that can execute a specified operation onlywhen specified multimedia data is presently being displayed.

[0120] Here, it is also possible to have a data display controlapparatus for receiving a plurality of sets of multimedia data, at leastone instruction, and at least one set of time control information, andcontrolling a display of the sets of multimedia data according to anoperation indication input by a user, wherein the plurality of sets ofmultimedia data compose a plurality of contents which make up abroadcast program, the instructions control a display of the sets ofmultimedia data, and each set of time control information relates to anexecution of an instruction, the data display control apparatusincluding: a data storage unit; a receiving unit for extracting at leastone set of multimedia data, at least one instruction, and at least oneset of time control information from data transmitted from a broadcastprogram transmission apparatus and storing the received sets ofmultimedia data, the received instructions, and the received sets oftime control information into the data storage unit; a current timeinformation obtaining unit for obtaining a set of current timeinformation for a current time; an operation indication receiving unitfor receiving the operation indication input by the user; a timeinformation judging unit for judging, when the operation indicationreceiving unit receives the operation indication, whether execution ofan arbitrary instruction is possible by comparing the set of timecontrol information related to the arbitrary instruction with the set ofcurrent time information; and a display control unit for executing thearbitrary instruction based on the judging result of the timeinformation judging unit.

[0121] With the stated construction, it is possible to realize a datadisplay control apparatus that can execute a specified operation inresponse to a user operation only after judging from a time element thatexecution should be performed.

[0122] The second object of the present invention can be achieved by adata transmission apparatus for transmitting a plurality of sets ofmultimedia data, wherein the plurality of sets of multimedia datacompose a plurality of contents which make up a broadcast program, thedata transmission apparatus including: a transmission data storage unitfor storing the plurality of sets of multimedia data and a set of timecontrol information used for controlling display of the plurality ofsets of multimedia data; and a transmission unit for transmitting theplurality of sets of multimedia data and the set of time controlinformation.

[0123] With the stated construction, it is possible to realize a datatransmission apparatus that can transmit to a data display controlapparatus sets of information indicating a display timing of multimediadata which composes a program, the program being a one-directionallytransmitted program that allows interactive operations to be made.

[0124] Here, the transmission unit may repeatedly transmit the set oftime control information.

[0125] With the stated construction, it is possible to realize a datatransmission apparatus that transmits data so that a data displaycontrol apparatus can soon obtain time information used for control of acontent, when a content which has been selected as a link destination atan arbitrary time by a user is to be displayed.

[0126] Here, the transmission data storage unit may further store a setof link information which shows interrelations between contents in theplurality of contents, and the transmission unit may also transmit theset of link information.

[0127] With the stated construction, it is possible to realize a datatransmission apparatus which transmits data that enables interactiveoperations to be made by the user for the display of contents.

[0128] Here, the data transmission apparatus of claim 17 also include: atime measuring unit for measuring a current time, wherein thetransmission unit further transmits a set of current time informationshowing the current time.

[0129] With the stated construction, it is possible to realize a datatransmission apparatus which transmits data that enables control of thetiming of display of multimedia data according to time information whichis correct for the data display control apparatus.

[0130] Here, the transmission data storage unit may store a timedifference value which indicates a time difference between the currenttime and a standard control time in the set of time control information,and the transmission unit may further transmit the time differencevalue.

[0131] With the stated construction, it is possible to realize a datatransmission apparatus which transmits data that displays multimediadata at the correct timing, even when there is a time difference betweenthe standard times of the control information for controlling thedisplay of multimedia data and the present time.

[0132] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing the plurality ofsets of multimedia data, at least one instruction for executing acertain operation, at least one set of time control information forcontrolling an execution of a related instruction, and a set of linkinformation which shows interrelations between contents in the pluralityof contents; and a transmission unit for transmitting the plurality ofsets of multimedia data, the instructions, the sets of time controlinformation, and the set of link information.

[0133] With the stated construction, it is possible to realize a datatransmission apparatus which transmits data for executing specifiedoperations at a given time.

[0134] Here, each of the instructions may control a display of a set ofmultimedia data.

[0135] With the stated construction, it is possible to realize a datatransmission apparatus which transmits data for enabling control ofoperation executions relating to the display of multimedia dataaccording to time.

[0136] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing the plurality ofsets of multimedia data, a plurality of sets of time control informationthat each correspond to one set of multimedia data and are used tocontrol a display of a corresponding set of multimedia data, and a setof link information which shows interrelations between contents in theplurality of contents; and a transmission unit for transmitting theplurality of sets of multimedia data, the plurality of sets of timecontrol information, and the set of link information.

[0137] With the stated construction, it is possible to realize a datatransmission apparatus that allows a data display control apparatus tocontrol display of multimedia data units based on time.

[0138] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing the plurality ofsets of multimedia data, a plurality of sets of time control informationthat each correspond to one content and are used to control a display ofa corresponding content, and a set of link information which showsinterrelations between contents in the plurality of contents; and atransmission unit for transmitting the plurality of sets of multimediadata, the plurality of sets of time control information, and the set oflink information.

[0139] With the stated construction, it is possible to realize a datatransmission apparatus that allows a data display control apparatus tocontrol display of content units based on time.

[0140] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing, the pluralityof sets of multimedia data, at least one instruction for controllingdisplay of the sets of multimedia data, at least one set of time controlinformation for automatically starting an execution of a relatedinstruction; and a set of link information which shows interrelationsbetween contents in the plurality of contents; and a transmission unitfor transmitting the plurality of sets of multimedia data, theinstructions, the sets of time control information, and the set of linkinformation.

[0141] With the stated construction, it is possible to realize a datatransmission apparatus that has a data display control apparatusautomatically perform display control at a predetermined time.

[0142] Here, each set of time control information may indicate a controltime which is an indicated time.

[0143] With the stated construction, it is possible to realize a datatransmission apparatus that transmits programs for which instructionsfor operations such as the display of multimedia data are executed ornot depending on time.

[0144] Here, each set of time control information may indicate a controlelapsed time showing an elapsed time from a start of display of apredetermined content.

[0145] With the stated construction, it is possible to realize a datatransmission apparatus that transmits data which enables a data displaycontrol apparatus to perform the display of multimedia data apredetermined time after displaying a predetermined content.

[0146] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing the plurality ofsets of multimedia data, at least one instruction for controlling adisplay of the sets of multimedia data, at least one set of time controlinformation, and a set of link information which shows interrelationsbetween contents in the plurality of contents, wherein each set of timecontrol information is composed of time information for an automaticstart of execution of one of the instructions and is related to agrouping of sets of multimedia data; and a transmission unit fortransmitting the plurality of sets of multimedia data, the instructions,the sets of time information, and the set of link information.

[0147] With the stated construction, it is possible to realize a datatransmission apparatus that enables a data display control apparatus toperform specified operations only when a specified set of multimedia iscurrently being displayed.

[0148] Here, it is also possible to have a data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatusincluding: a transmission data storage unit for storing the plurality ofsets of multimedia data, at least one instruction for controlling adisplay of the sets of multimedia data, at least one set of time controlinformation which is used as a criterion by a reception apparatus injudging whether to execute a related instruction; and a set of linkinformation which shows interrelations between contents in the pluralityof contents; and a transmission unit for transmitting the plurality ofsets of multimedia data, the instructions, the sets of time controlinformation, and the set of link information.

[0149] With the stated construction, it is possible to realize a datatransmission apparatus that enables a data display control apparatus toperform specified operations in response to user operations based on thetime at which the user operations are made.

[0150] The third object of the present invention can be achieved by adata display control information editing apparatus for displayinginterrelations between a plurality of contents on a display screen andfor editing, in accordance with a user operation, sets of time-relatedinformation that are used for controlling the interrelations, the datadisplay control information editing apparatus including: a data storageunit for storing a plurality of pairings of a set of link informationand a set of valid period information and storing a set of contentcontrol information, wherein each set of link information indicates achange in display from a first content to a second content, each set ofvalid period information indicates a valid period of a corresponding setof link information, and the set of content control information is usedfor controlling display and processing of contents; a time receivingunit for receiving an indicated time input by a user; and a contentrelation displaying unit for displaying interrelations between contentsat the indicated time received by the time receiving unit, based on thepairings of a set of link information and a set of valid periodinformation which has a valid period that includes the indicated timereceived by the time receiving unit.

[0151] With the stated construction, it is possible to realize a datadisplay control information editing apparatus that allows the user tounderstand the links between contents at a glance, and allows the userto see what links are valid at a time indicated by the user.

[0152] Here, the data display control information editing apparatus mayalso include: a content specification receiving unit for receiving aspecification of a content input by a user; and a link informationupdating unit for updating a set of valid period information of a set oflink information which indicates a change in display to the contentspecified by the user so that the set of link information is madeinvalid at the indicated time received by the time receiving unit.

[0153] With the stated construction, it is possible to realize a datadisplay control information editing apparatus which generates controlinformation that prevents the display of an indicated content after atime indicated by the user by severing a link from a content to theindicated content.

[0154] Here, the sets of link information and the sets of valid periodinformation are transmitted from a transmission apparatus used in adigital broadcast system to a data display control apparatus whichdisplays contents.

[0155] With the stated construction, it is possible to realize a datadisplay control information editing apparatus which generates controlinformation that has a specified operation executed at a specified timeby a data display control information editing apparatus that receives adigital broadcast.

BRIEF DESCRIPTION OF THE INVENTION

[0156] These and other objects, advantages and features of the inventionwill become apparent from the following description thereof taken inconjunction with the accompanying drawings which illustrate a specificembodiment of the invention. In the drawings:

[0157]FIG. 1 shows the construction of a digital broadcasting system ofthe related art;

[0158]FIG. 2 shows an example of images displayed by the data receptionapparatus in the digital broadcasting system of the related art;

[0159]FIG. 3 is a simplified representation of the data transmitted bythe data transmission apparatus of the related art;

[0160]FIG. 4 is a more detailed representation of the data transmittedby the data transmission apparatus of the related art;

[0161]FIG. 5 shows the multiplexing of the data transmitted by the datatransmission apparatus in the related art;

[0162]FIG. 6 shows the data construction of the navigation information216 in the related art;

[0163]FIG. 7 is a block diagram showing the construction of the datadisplay control apparatus in the first embodiment of the presentinvention;

[0164]FIG. 8 shows examples of images displayed by the data displaycontrol apparatus 1000 in the first embodiment of the present invention;

[0165]FIG. 9 is a simplified representation of the data transmitted bythe data transmission apparatus;

[0166]FIG. 10 is a more detailed representation of the data transmittedby the data transmission apparatus FIG. 11 shows the data constructionof the navigation information 2160;

[0167]FIG. 12 shows the data construction of the navigation information2260;

[0168]FIG. 13 shows the data construction of the navigation information2360;

[0169]FIG. 14 is a flowchart for a content switching operation and theactivation of a handler;

[0170]FIG. 15 shows the transformation in the display screen;

[0171]FIG. 16A shows the data construction of the TDT;

[0172]FIG. 16B shows the data construction of the TOT;

[0173]FIG. 17 shows the data construction of the navigation information2170;

[0174]FIG. 18 shows the data construction of the navigation information2270;

[0175]FIG. 19 shows the data construction of the navigation information2370;

[0176]FIG. 20 is a flowchart for the operation for the activation of ahandler in the second embodiment;

[0177]FIG. 21 shows the transformation in the display screen in thesecond embodiment;

[0178]FIG. 22 shows the data construction of the navigation information2180;

[0179]FIG. 23 is a flowchart showing a content switching operation andthe activation of a handler in the third embodiment;

[0180]FIG. 24 shows the data construction of the navigation information6160;

[0181]FIG. 25 is a flowchart showing a content switching operation andthe activation of a handler in the fourth embodiment;

[0182]FIG. 26 shows the changes in the display screen in the fourthembodiment;

[0183]FIG. 27 shows the data construction of the navigation information7160;

[0184]FIG. 28 is a flowchart showing a content switching operation andthe activation of a handler in the fifth embodiment;

[0185]FIG. 29 shows examples of images displayed by the data displaycontrol apparatus 1000 in the sixth embodiment of the present invention;

[0186]FIG. 30 is a simplified representation of the data transmitted bythe data transmission apparatus;

[0187]FIG. 31 shows the data construction of the navigation information8160;

[0188]FIG. 32 is a flowchart showing a content switching operation andthe activation of a handler;

[0189]FIG. 33A shows the transformation in the display screen when theuser gives his/her answer within the time limit of a quiz;

[0190]FIG. 33B shows the transformation in the display screen when theuser does not give his/her answer within the time limit of a quiz;

[0191]FIG. 34 is a block diagram showing the construction of the datadisplay control information editing apparatus of the seventh embodimentof the present invention;

[0192]FIG. 35 is a flowchart showing the operation of the data displaycontrol information editing apparatus 10000;

[0193]FIG. 36 shows an example display for the display screen of thedata display control information editing apparatus 10000;

[0194]FIG. 37 is a block diagram showing the construction of the datadisplay control information editing apparatus in the eighth embodimentof the present invention; and

[0195]FIG. 38 is a flowchart showing the operation of the data displaycontrol information editing apparatus 10500 in the eighth embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

[0196] The first embodiment of the present invention relates to a datatransmission apparatus that broadcasts programs for which specifiedoperations can be performed at a specified time, and to a data displaycontrol apparatus which receives transmitted data and performs thespecified operations at indicated times. This first embodiment of thepresent invention is described in detail below, with reference to thedrawings.

[0197] The data display control apparatus of the first embodiment of thepresent invention is an apparatus which receives an MPEG2 transportstream transmitted by a transmission apparatus for a digital broadcastand interactively separates and reproduces contents from the MPEG2transport stream in accordance with user operations.

[0198] The term “content” is used to express the unit of information forwhich interactive operations can be performed by the user. Here, eachcontent is composed of presentation information and navigationinformation. The presentation information is composed of image data andaudio data. The navigation information is composed of bitmap data forbuttons that are used to compose on-screen display graphics that aredisplayed superimposed onto the various kinds of image data, scriptsthat represent the operation processing to be performed in response touser operations, and hyperlinks that express the contents for the linkdestinations to which the display can be switched in accordance withuser operations. The transmission data is formed by multiplexing thepresentation information and navigation information, and is repeatedlytransmitted by the data transmission apparatus in the first embodimentas a MPEG2 transport stream in accordance with MPEG2 (Moving PicturesExperts Group Phase2) standards.

[0199] It should be noted here that the data transmission apparatus inthe first embodiment performs transmission of at least one MPEG2transport stream on a variety of bandwidths for a same satellite(network), in the same way as a conventional digital satellitebroadcasting system. Here, all of the broadcast programs are multiplexedinto the MPEG2 transport streams.

Construction of the Data Display Control Apparatus

[0200] The following is an explanation of the construction of the datadisplay control apparatus in the first embodiment of the presentinvention.

[0201] The construction of the data display control apparatus of thefirst embodiment is shown by the block diagram in FIG. 7. As shown inthe figure, the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100.

[0202] The reception unit 1010 receives the MPEG2 transport stream andoutputs it to the TS decoder unit 1020. It should be noted here that theindication of the MPEG2 transport stream is performed using identifiersaccording to control by the reception control unit 1050.

[0203] The TS decoder unit 1020 includes a filter condition storage unit1021 for storing the filter conditions specified by the receptioncontrol unit 1050, and operates in accordance with these filterconditions so as to only separate image data or audio data withidentifiers indicated by the reception control unit 1050 from thetransport stream outputted by the reception unit 1010. The TS decoderunit 1020 outputs the separated data to the AV decoder unit 1030. The TSdecoder unit 1020 also separates table data with identifiers specifiedby the reception control unit 1050 and outputs the table data to thereceived data storage unit 1040. The TS decoder unit 1030 also separatesa PCR (Program Clock Reference) and outputs it to the AV decoder unit1030.

[0204] The filter condition storage unit 1021 is capable ofsimultaneously storing a plurality of filter conditions and the TSdecoder unit 1020 is capable of performing a plurality of separationsbased on the filter conditions in parallel. Here, the term “filtercondition” refers to indication information, such as the stream IDs andtable IDs for separating image data, audio data, navigation information,PCRs, and other control information, output destinations for theseparated data, and control information which start or stops separationoperations.

[0205] The AV decoder unit 1030 includes a clock unit 1031 and aninternal buffer, and on receiving image data and/or audio data from theTS decoder unit 1020, stores the data in its internal buffer. The AVdecoder unit 1030 then decodes the image data and/or audio data in thepredetermined decoding units in accordance with instructions from thereception control unit 1050 and outputs the decoded data to thereproduction unit 1060 in synchronization using the clock unit 1031.

[0206] The clock unit 1031 is set at a standard time using the value ofthe PCR outputted by the TS decoder unit 1020 and is used to measuretime that is used as the standard to ensure that image data and audiodata are decoded in synchronization.

[0207] The received data storage unit 1040 can be composed of RAM, forexample, and includes a stream correspondence storage unit 1041, anavigation information storage unit 1042, a system information tablestorage unit 1043, and a time information storage unit 1044. It shouldbe noted here that the stream correspondence storage unit 1041 is thesame as the stream correspondence table storage unit 132 in the relatedart, the navigation information storage unit 1042 is the same as thenavigation information table storage unit 133, and the systeminformation storage unit 1043 is the same as the system informationtable storage unit 134.

[0208] The stream correspondence storage unit 1041 has an area forstoring information showing the multiplexing units in the stream for theimages and audio which compose each content, with this area storing setsof stream correspondence information VET which are information showingthe relationship between VE_ids, which are identifiers for videoelements (VE) which are units of information for image data, andmultiplexing units for VEs in the stream. Accordingly, the identifierVE_id is used to specify the image data to be displayed.

[0209] In the same way, the navigation information storage unit 1042 hasan area for storing navigation information, the system informationstorage unit 1043 has an area for storing system information such as thePAT and PMT and the time information storage unit 1044 has an area forstoring the TOT and the TDT.

[0210] The PAT (Program Association Table) referred to here isinformation for managing a plurality of broadcast programs in accordancewith MPEG2 system standard. The PAT includes PIDs which are identifiersfor separating a PMT for each program, with the PID of the PAT itselfbeing predetermined as “0”.

[0211] As a result, the data display control apparatus can separate thePAT from the transmitted data by setting the PID “0” in the filtercondition storage unit 1021, with the separated PAT being stored in thesystem information storage unit 1043.

[0212] The PMT (Program Map Table) is information for managing thevarious kinds of information required by one broadcast program inaccordance with MPEG2 system standard. The PMT includes the PIDs thatare the identifiers used for separating the PCR, the image data, andnavigation information, and identifiers for the image data andnavigation information of the content which is to be displayed firstwhen the present program is selected.

[0213] When a program is selected by the user of the data displaycontrol apparatus, the data display control apparatus refers to the PATto obtain the PID of the PMT corresponding to the selected program andsets this PID in the filter condition storage unit 1021 to separate thePMT which it then stores in the system information storage unit 1043.

[0214] The TDT (Time and Data Table) is information showing a standardtime for the present date and time, while the TOT (Time Offset Table) isinformation showing a time difference for different countries. This TDTand TOT are described in more detail later in this specification.

[0215] The signal reception unit 1100 receives a signal for a useroperation sent from a remote controller or the like, and informs thereception control unit 1050 of the received signal.

[0216] The reproduction unit 1060 superimposes on-screen displaygraphics information outputted by the reception control unit 1050 ontothe image data decoded by the AV decoder unit 1030 in accordance withindications from the reception control unit 1050, and outputs a combinedimage to the display unit 1070. The reproduction unit 1060 also outputsthe audio data decoded by the AV decoder unit 1030 to the audio outputunit 1080.

[0217] The display unit 1070 can be realized by a CRT or liquid crystaldisplay, and is used to display the images outputted by the reproductionunit 1060.

[0218] The audio output unit 1080 can be realized by a speaker, andoutputs the audio outputted by the reproduction unit 1060.

[0219] The reception control unit 1050 has a bytecode interpreter 1051,and controls the reception unit 1010, the TS decoder unit 1020, the AVdecoder unit 1030, and the reproduction unit 1060 to receive the desiredtransport stream, to reset the filter conditions in the filter conditionstorage unit 1021 for the data to be separated, and to reproduce thedesired images and audio. The reception control unit 1050 also performsa variety of operations in response to user operations.

[0220] In accordance with a user operation, the reception control unit1050 refers to the navigation information in the navigation informationstorage unit 1042, outputs the on-screen display graphics to bedisplayed superimposed on the image data to the reproduction unit 1060,and, when a button operation is made by the user, executes thecorresponding handler processing. Here, buttons are displayed on thedisplay screen using these on-screen display graphics and are displayedbased on bitmap information (or the like) given in the navigationinformation. The handler processing referred to here is an operationwhich is executed corresponding to the occurrence of an event, and isperformed based on the scripts given in the navigation information.

[0221] The bytecode interpreter 1051 interprets the scripts given in thenavigation information one by one and executes them.

Data Composition of the Contents and the Display Screen

[0222] The following is an explanation of the display screen of the datadisplay control apparatus 1000 which displays the contents and of thedata which composes each content, with reference to FIGS. 8, 9, 10, and11.

[0223]FIG. 8 shows an example of the screen displayed by the datadisplay control apparatus 1000 in the first embodiment of the presentinvention. This figure corresponds to FIG. 2 of the related art sectionand shows an example of a mail order program. FIG. 8 shows a content2100 which displays a mail order menu, a content 2200 which displaysinformation about video equipment, and a content 2300 which displaysinformation about stereo equipment. Here, switching is possible betweenthese contents 2100, 2200, and 2300 in accordance with user operations,as shown by the arrows 2400, 2410, 2420, and 2430. The difference withFIG. 2 is that content 2130 is provided as the same content as content2100 after a given time period has passed.

[0224] When the content 2100 representing the mail order menu isdisplayed on the display screen and the user selects and activates the“Video” button 2110, the display switches as shown by the arrow 2400from content 2100 to content 2200 which displays information about videoequipment. If the user then selects and activates the “Menu” button2210, the display switches as shown by the arrow 2410 back from thecontent 2200 to the content 2100.

[0225] In the same way, when the content 2100 representing the mailorder menu is displayed on the display screen and the user selects andactivates the “Stereo” button 2120, the display switches as shown by thearrow 2430 from content 2100 to content 2300 which displays informationabout stereo equipment. If the user then selects and activates the“Menu” button 2310, the display switches as shown by the arrow 2420 backfrom the content 2300 to the content 2100. Here, contents 2100, 2200,and 2300 are provided with buttons 2110, 2120, 2210, and 2310 to allowthe user to make the interactive operations which switch the display asdescribed.

[0226] When the time 15:00:00 on Sep. 9, 1996 is reached, the display ofthe content 2100 is changed to become displayed as the content 2130where the button “This offer is no longer valid” is displayed. Thisbutton 2131 is displayed according to data which is already included aspart of content 2100.

Data Transmission Apparatus

[0227] The following is an explanation of the transmission of the datacomposing each content by the data transmission apparatus in the digitalbroadcasting system of the first embodiment of the present invention. Itshould be noted here that the data transmission apparatus of the firstembodiment has the same construction as the data transmission apparatus101 (see FIG. 1) described in the related art section. However, unlikethe related art, information is included in the transmitted navigationinformation to enable control according to a time element, with thecontent of this navigation information being described later in thisspecification.

[0228]FIG. 9 is a simplified representation of the data transmitted fromthe data transmission apparatus. This figure corresponds to FIG. 3 inthe related art section, with the transmitted data 2010 corresponding todata 201 in FIG. 3, the image data 2150, 2250, and 2350 corresponding toimage data 215, 225, and 235 in FIG. 3, and the navigation information2160, 2260, and 2360 corresponding to data 216, 226, and 236 in FIG. 3.

[0229] Each set of image data 2150, 2250, and 2350 represents abackground image for the contents 2100, 2200, and 2300 which aredisplayed on the display screen of the data display control apparatus1000.

[0230] The difference between FIG. 3 and FIG. 9 lies in the inclusion ofcontrol information called “Time_Event” in each set of navigationinformation in FIG. 9. It should also be noted here that unlike FIG. 3,the navigation information 2160 in FIG. 9 includes a bitmap for a buttonstating “This offer is no longer valid” which has an attribute showingthat it is invisible in its initial state.

[0231] The content 2100 shown in FIG. 8 is expressed by the image data2150 and the navigation information 2160. Likewise, the content 2200 isexpressed by the image data 2250 and the navigation information 2260,and the content 2300 is expressed by the image data 2350 and thenavigation information 2360.

[0232] The data transmission apparatus repeatedly transmits the data2010 in a predetermined cycle. This transmission is the same as thatdescribed in the related art section with reference to FIG. 4, with theimage data and navigation information of FIG. 4 being replaced by theimage data and navigation information shown in FIG. 9.

[0233] The following is a detailed explanation of the data which ismultiplexed and transmitted by the data transmission apparatus. Arepresentation of the multiplexing of the data to be transmitted by thedata transmission apparatus is shown in FIG. 10.

[0234]FIG. 10 corresponds to FIG. 5 of the related art section, so thatimage data VE(N), navigation information NE(N), stream correspondenceinformation VET(N), and system information such as a PCR, PAT, and PMTsare multiplexed into the transmission data. This system informationfurther includes a TDT and TOT which are given predetermined PIDs.

[0235] Since the data transmission apparatus of the first embodimenttransmits the data as described above, the data display controlapparatus 1000 can have the TS decoder unit 1020 separate the TDT andTOT from the transmitted transport stream by setting the PIDs which arepredetermined for the TDT and TOT into the filter condition storage unit1021.

Detailed Description of the Navigation Information

[0236] The following is an explanation of the navigation informationwhich was shown in outline in FIG. 9, with reference to FIGS. 11 to 13.

[0237]FIG. 11 shows the data construction of the navigation information2160. This navigation information 2160 includes a Time_Event_Part 2161,a Bytecode_Part 2162, a Handler_Part 2163, a Graphics_Property_Part2164, a Bitmap_Information_Part 2165, and a Hyperlink_Information_Part2166.

[0238]FIG. 11 corresponds to FIG. 5 in the related art section anddiffers from the related art by including a Time_Event_Part 2161 whichis characteristic to the present invention.

[0239] The Time_Event_Part 2161 corresponds to the part in FIG. 9 shownas “Time_Event”, and is information which shows that a specified handleris to be activated at an indicated time. In the example in FIG. 11, thehandler with the handler number “2” is activated at 15:00:00 on Sep. 9,1996. It should be noted here that several activation times may be givenfor a same handler. In the present example, this activation time isgiven in year, month, day, hour, minute, second order.

[0240] The Bytecode_Part 2162 corresponds to the part in FIG. 9 shown as“Script”, and is the information used for recording bytecodes which area kind of script. These bytecodes include an instruction set, such asconditional branches, integer calculations, and access toconstants/variables, which allows basic programming, and a variety ofinstruction sets that are related to the control of image and audiodata.

[0241] In the example in FIG. 11, the bytecode with bytecode number “0”is “Push L0, GotoPage”. Here, “Push L0” is an instruction whichrepresents the storing of the value “0” in the stack, while “GotoPage”is an instruction indicating a switch of display to the content shown bythe link number whose value is stored in the stack. Here, the linknumber is given in the Hyperlink_Information_Part, and is an identifierfor identifying a content to be switched to.

[0242] The bytecode with bytecode number “2” is “SetGraphicVisibility”,with this being an instruction that switches between “visible” and“invisible” states depending on whether “0” or “1” is stored in thestack, these states being for a button indicated by a value in the stackthat precedes the value indicating “visible” or “invisible”.

[0243] Accordingly, the bytecode with the bytecode number “0” indicatesa switching of the display to the content which is the link destinationfor link number “0”, while the bytecode with the bytecode number “1”indicates a switching of the display to the content which is the linkdestination for link number “1”. The bytecode with the bytecode number“2”, meanwhile, makes the button with the graphics number “2” visible,while making the buttons with the graphics numbers “0” and “1”invisible. Graphics numbers are dealt with in more detail in thedescription of the Graphics_Property_Part given later in thisspecification.

[0244] The Handler_Part 2163 is the information which records thecorrespondence between handler numbers and bytecode numbers. In theexample in FIG. 11, handler numbers 0, 1, and 2 respectively correspondto bytecode numbers 0, 1, and 2. It should be noted here that not onlybytecodes, but also information defining the processing environment ofhandlers, such as variable areas, is given corresponding to thehandlers, although such information is not especially related to thepresent invention and has therefore not been illustrated.

[0245] The Bitmap_Information_Part 2165 is the part used to record thecontent of the bitmaps which display buttons corresponding to thegraphics numbers. In the example in FIG. 11, the graphics with thenumber “0” represent the bitmap “Video”, while the graphics with thenumber “1” represent the bitmap “Stereo”, and the graphics with thenumber “2” represent the bitmap “This offer is no longer valid”.

[0246] The Graphics_Property_Part 2164 is information for composing theon-screen display graphics to be displayed superimposed onto the videodata on the display screen, and so includes graphics numbers foridentifying sets of graphics, graphics types, display coordinates forsets of graphics, a handler number associated with the graphics, and anentry showing the initial state for when the content is displayed. Forthe example in FIG. 11, the type for each set of graphics is “button”,with graphics numbers 0, 1, and 2 corresponding to the graphics in theBitmap_Information_Part 2165 with the same values “0”, “1”, and “2”. Inthe present example, button 0, button 1, and button 2 are displayed withthe x and y coordinates respectively given as (20,20), (20,60), and(0,20). The handler numbers of the handlers which are activated onselection and activation of the buttons 0 and 1 are given as “0” and“1”, while no handler is given corresponding to button 2. Also, theinitial states of button 0 and button 1 when the content is displayedare given as “visible”, while the initial state of button 2 is given as“invisible”.

[0247] The Hyperlink_Information_Part 2166 is information that recordsthe IDs of the materials which compose contents for link destinations.Here, IDs for materials are given as the information showing all of thecontents that are link destinations for the content to which the presentnavigation information belongs. Here also, link numbers are given toidentify the sets of identifiers which identify each of the linkdestination contents. For the example shown in FIG. 11, “NE_id=1,VE_id=1” is recorded for the link destination with the link number “0”,showing that the content which is composed of the information with theVE_id “1” and the NE_id “1” is a link destination. Here, information isalso recorded showing that the content which is composed of theinformation with the VE_id “2” and the NE_id “2” is the link destinationfor the link number “1”.

[0248] It should be noted here that NE_id given as “0” at the top ofFIG. 11 shows that the navigation information being explained here isthe navigation element which has the ID FIG. 12 shows the dataconstruction of the navigation information 2260. The NE_id of thisnavigation information is “1”, and the data construction is the same asnavigation information 2160 described above. The content of thisnavigation information 2260 in FIG. 12 is described in detail below.

[0249] The Time_Event_Part 2261 contains no information.

[0250] The Bytecode_Part 2262 records that the bytecode with thebytecode number “0” is “PushL0, GotoPage”, which is an exampleinstruction that displays the content which is the link destination withthe link number “0”.

[0251] The Handler_Part 2263 shows that the handler number “0”corresponds to the bytecode number “0”.

[0252] The Bitmap_Information_Part 2265 shows that the bitmap for “Menu”has been assigned the bitmap number “0”.

[0253] The Graphics_Property_Part 2264 shows that the graphics type is“button”, and that the graphics number is “0”. The x and y coordinatesfor displaying button 0 are given as (20,60). The handler which isactivated on the activation of button 0 is given as handler number 0,with the button 0 being visible in the initial state when the presentcontent is displayed.

[0254] The Hyperlink_Information_Part 2266 records “NE_id=0, VE_id=0” asthe link destination with the link number “0”, and so shows that thecontent which is composed of the information with the NE_id “0” and theVE_id “0” is a link destination.

[0255]FIG. 13 shows the data construction of the navigation information2360. The NE_id of this navigation information is “2”, and the dataconstruction is the same as navigation information 2160 described above.The content of this navigation information 2360 in FIG. 13 is describedin detail below.

[0256] The Time_Event_Part 2361 contains no information.

[0257] The Bytecode_Part 2362 records that the bytecode with thebytecode number “0” is “PushL0, GotoPage”, which is an exampleinstruction that displays the content which is the link destination withthe link number “0”.

[0258] The Handler_Part 2363 shows that the handler number “0”corresponds to the bytecode number “0”.

[0259] The Bitmap_Information_Part 2365 shows that the bitmap for “Menu”has been assigned the bitmap number “0”.

[0260] The Graphics_Property_Part 2364 shows that the graphics type is“button”, and that the graphics number is “0”. The x and y coordinatesfor displaying button 0 are given as (20,60). The handler which isactivated on the activation of button 0 is given as handler number 0,with the button 0 being visible in the initial state when the presentcontent is displayed.

[0261] The Hyperlink_Information_Part 2366 records NE_id=0, VE_id=0 asthe link destination with the link number “0”, and so shows that thecontent which is composed of the information with the NE_id “0” and theVE_id “0” is a link destination.

[0262] Each content is composed of navigation information, with the datacomposition described above, and image data, and is displayed on adisplay screen of a data reception apparatus.

[0263] It should be noted here that the image data which corresponds tothe VE_id=0 is image data 2150, while the image data which correspondsto the VE_id=1 is image data 2250, and the image data which correspondsto the VE_id=2 is image data 2350 (see FIG. 9).

[0264] Using the data described above, when the user selects andconfirms a button for a content displayed by the data display controlapparatus 1000, the display switches to another content. When the timegiven in the Time_Event_Part is reached, control is also performed toexecute the specified operation.

Operation of the Data Display Control Apparatus

[0265] The following is an explanation of the operation of the receptioncontrol unit 1050 of the data display control apparatus 1000 based onthe data construction described above. This explanation refers to FIGS.14 and 15.

[0266]FIG. 14 is a flowchart showing a content switching operation andthe activation of a handler, and FIG. 15 shows the transformation in thedisplay screen.

[0267] The reception control unit 1050 is composed of a CPU and aprogram, and performs the processing for content switching and theactivation of handlers. This processing is achieved according to theflow in FIG. 14. In the initial process in S3010, the content to bedisplayed at the start of the reception of a program is indicated. Whenit is judged in S3020 that a content switching operation is to be made,the processes in S3030, S3040, and S3050 or S3060 are performed. Afterthis, it is judged in S3070 whether there is a handler to be activatedat an indicated time, with the processes S3080 to S3100 being performedin such case. Processes S3110 and S3120 are then performed correspondingto user inputs, and in S3130 is performed to activate a handler.

[0268] The information for the first content to be displayed is set as apair of a VE_id and an NE_id in the PMT stored in the system informationstorage unit 1043. The following example focuses on the case where theinformation VE_id=0 and NE_id=0 is given in the PMT. The explanationalso supposes that the present operation starts at 14:57:00 on Sep. 9,1996.

[0269] First, the information VE_id=0 and NE_id=0 is read from the PMTas the information for the first content to be displayed for the presentmail order program (step S3010). Since this is the first content, thesystem considers that content switching has been performed (S3020:Yes)and so displays the present content (S3030).

[0270] The display of this first content is achieved by displaying theimage data 2150 with the VE_id=0 as the background image and on-screendisplay graphics in accordance with the content of the navigationinformation with the NE_id=0. Here, the button “Video” is visiblydisplayed at a position given by the coordinates (20,20) and the button“Stereo” is visibly displayed at a position given by the coordinates(20,60), in accordance with the content of the Graphics_Property_Part2164 and the Bitmap_Information_Part 2165 of the navigation informationshown in FIG. 11. This results in the display shown as 3210 in FIG. 15.

[0271] Once the present content has been displayed, the receptioncontrol unit 1050 judges whether there is a time indication foractivating a handler in the Time_Event_Part of the NE (S3040), in whichcase the time indication flag for handler activation processing inresponse to time is set at “1” (S3050). When there is no timeindication, the time indication flag is set at “0” (S3060). Here, sincethe handler with the handler number “2” in the Time_Event_Part of thenavigation information shown in FIG. 11 is set as being activated at15:00:00 on Sep. 9, 1996, the time indication flag is set at “1”(S3050).

[0272] When the time indication flag has been set at “1” (S3070:Yes),the reception control unit 1050 obtains the present time (S3080) andadjusts the present time using the time difference set for the countryin which the data display control apparatus 1000 is located (S3090). Theacquisition of the time difference and adjustment of the present timeare described in more detail later in this specification. In the presentexample, however, there is no time difference.

[0273] The reception control unit 1050 judges whether the present timehas reached the time indicated in the Time_Event_Part 2161 of thepresent navigation information NE (S3100), and if not, advances to theprocessing for the movement of the selection pointer in accordance withuser inputs (S3110). When one of the buttons has been selected andactivated by the user (S3120:Yes), the corresponding handler isactivated (S3130). The selection pointer referred to here is a markwhich is displayed on the display screen that can be moved in accordancewith user operations. As a result, the user can move the selectionpointer to indicate a desired button using cursor keys provided, forexample, on a remote controller, with the indicated button beingselected and activated when the user presses the “Enter” key.

[0274] In the present example, the user selects the “Video” button, sothat the reception control unit 1050 refers to theGraphics_Property_Part 2164 and activates the handler with the handlernumber “0”. This handler is composed of the bytecode with the bytecodenumber “0” whose content is “PushL0, GotoPage”. As a result, the displayswitches to the content which is the link destination of the link number“0”, with this content being expressed by “VE_id=1, NE_id=1 ” in theHyperlink_Information_Part 2166. Here, bytecodes are executed by thereception control unit 1050 using the bytecode interpreter 1051.

[0275] The bytecode interpreter 1051 has a stack area for storingvariables, and in the present case interprets “Push L0” and stores thevalue “0” in the stack area. After this, the bytecode interpreter 1051interprets “GotoPage” and performs content switching for the link numbercorresponding to the value stored in the stack area.

[0276] After the activation of a handler (S3130), the processing returnsto the judgement of whether content switching has been performed(S3020), and since this is the case, the new content is displayed(S3030).

[0277] The display of this next content is achieved by displaying theimage data 2250 with the VE_id=1 as the background image and on-screendisplay graphics in accordance with the content of the navigationinformation with the NE_id=1. Here, the button “Menu” is visiblydisplayed at a position given by the coordinates (20,60), in accordancewith the content of the Graphics_Property_Part 2264 and theBitmap_Information_Part 2265 in the navigation information NE shown inFIG. 12.

[0278] The time when this next content is displayed is 14:58:00 on Sep.9, 1996, so that the display screen becomes as shown by 3220 in FIG. 15.

[0279] After the content display process has been performed (S3030), thereception control unit 1050 judges whether there is a time indication inthe Time_Event_Part of the present NE (S3040). Since the Time_Event_Part2261 of the navigation information NE in FIG. 12 does not include anytime indications, the reception control unit 1050 sets the timeindication flag at “0” (S3060).

[0280] Since the time indication flag is “0” (S3070), the receptioncontrol unit 1050 skips the time judgement processes (S3080 to S3100),and performs the processing for user inputs (S3110, S3120), with acorresponding handler being activated in S3130 when a button has beenselected and activated.

[0281] When the user selects and activates the “Menu” button, thereception control unit 1050 refers to the Graphics_Property_Part 2264and activates the handler with the handler number “0” . This handler iscomposed of the bytecode with the bytecode number “0” whose content is“PushL0, GotoPage”. As a result, the display switches to the contentwhich is the link destination of the link number “0”, with this contentbeing expressed by “VE_id=0, NE_id=0” in the Hyperlink_Information_Part2266.

[0282] After the activation of a handler (S3130), the processing returnsto the judgement of whether content switching has been performed(S3020), and since this is the case, the new content is displayed(S3030).

[0283] This new content is the same as the content which was displayedinitially, and so is achieved by displaying the image data 2150 with theVE_id=0 as the background image and -15 on-screen display graphics inaccordance with the content of the navigation information with theNE_id=0.

[0284] The time when this next content is displayed is 14:59:00 on Sep.9, 1996, so that the display screen becomes as shown by 3230 in FIG. 15.

[0285] After the content display process has been performed thereception control unit 1050 judges that there is the time indication15:00:00 on Sep. 9, 1996 for the handler with the handler number “2” inthe Time_Event_Part 2161 of the navigation information shown in FIG. 11,and so sets the time indication flag at “1” (S3050).

[0286] Since the time indication flag is “1” (S3070), the receptioncontrol unit 1050 obtains the present time (S3080) and adjusts thepresent time using the time difference set for the country in which thedata display control apparatus 1000 is located (S3090).

[0287] The reception control unit 1050 next judges whether the presenttime has reached the time indicated by the Time_Event_Part 2161 of thenavigation information NE (S3100).

[0288] If the present time reaches 15:00:00 on Sep. 9, 1996, thereception control unit 1050 activates handler 2. In more detail, thereception control unit 1050 refers to the Handler_Part 2163 and theBytecode_Part 2162 of the navigation information NE shown in FIG. 11,and has the set of bytecodes “PushL2, PushL1, SetGraphicVisibility,PushL0, PushL0, SetGraphicVisibility, PushL1, PushL0,SetGraphicVisibility” executed by the bytecode interpreter 1051.

[0289] The bytecode interpreter 1051 first interprets “PushL2” andstores the value “2” in the stack, before interpreting “PushL1” andstoring the value “1” in the stack. The bytecode interpreter 1051 nextinterprets “SetGraphicVisibility” and, since this is an instructionwhich sets the state of visibility or invisibility for graphicsindicated by the second operand in accordance with the value of thefirst operand, extracts the first variable “1” from the stack indicatingvisibility and the second variable “2” from the stack indicating thegraphics with the graphics number “2”, before setting the graphics withthe graphics number “2” as visible.

[0290] Following this, the bytecode interpreter 1051 interprets thebytecode “PushL0, PushL0, SetGraphicVisibility” and makes the graphicswith the graphics number “0” invisible, and then interprets the bytecode“PushL1, PushL0, SetGraphicVisibility” and makes the graphics with thegraphics number “1” invisible.

[0291] As a result of the above processing, the bytecode interpreter1051 of the reception control unit 1050 makes the “This offer is nolonger valid” button visible, while making the “Video” and “Stereo”buttons invisible so that the display screen changes to the displayshown as 3240 in FIG. 15.

[0292] By operating as described above, the data display controlapparatus 1000 is able to process the specified handler at the indicatedtime.

Acquisition of the Present Time and Adjustment for Time Difference

[0293] The following is a detailed description of the acquisition of thepresent time and the adjustment of time difference by the data displaycontrol apparatus 1000.

[0294]FIGS. 16A and 16B show the data constructions of the TDT and theTOT. The information given in brackets shows examples of the content ofthese tables.

[0295] The TDT is the table which stores the present time which, asshown in FIG. 16A, is given in year, month, day, hour, minute, secondformat. In the present example, the time 1996/9/9 15:00:00 is given inthe TDT with this data being transmitted at the time corresponding toits content. Here, the actual data is stored using a BCD (Binary CodedDecimal) code.

[0296] The TOT, meanwhile, stores the present time and a plurality oftime difference entries for different country codes. Here, country codesare predetermined codes for identifying countries. A country code isalso permanently stored within the data display control apparatus 1000.The time differences are expressed as plus or minus a time given ashours, minutes, seconds. In the present example, the time difference forthe U.K. is given as “0” and the time difference for Japan is given as“+9 hours”. As a result, the data display control apparatus 1000 is ableto find the time difference for the country code which matches its owncountry code, and so can perform adjustment for the time difference.

[0297] The TDT and TOT are assigned predetermined PIDs and aresuccessively transmitted from the data transmission apparatus as timeprogresses.

[0298] Here, when the data display control apparatus 1000 needs to knowthe present time, the reception control unit 1050 sets the predeterminedPID into the filter condition storage unit 1021, and the received timeinformation is stored in the time information storage unit 1044 in thereceived data storage unit 1040 via the reception unit 1010 and the TSdecoder unit 1020. This time information is then used by the receptioncontrol unit 1050.

[0299] The reception control unit 1050 obtains the TDT and the TOT inS3080 as described above. In S3090, the reception control unit 1050refers to the country code permanently stored in the data displaycontrol apparatus 1000 and converts the time into the time for thecountry in which the data display control apparatus 1000 is located.

[0300] In S3100, the reception control unit 1050 compares the presenttime with the time indicated in the Time_Event_Part of the presentnavigation information NE. In this first embodiment, the time given inthe Time_Event_Part is set as the time for the country in which the datadisplay control apparatus 1000 is located. It should be noted here thatregardless of how the standard time is set, the handler can be activatedat the proper time by performing compensation for time when comparingthe standard time to the present time.

[0301] Here, the time difference referred to by the compensation fortime difference is a difference between a the respective standard timesof the current time and the time given in the Time_Event_Part.

[0302] With the data display control apparatus of this first embodimentof the present invention, handlers can be activated at their indicatedtime. Here, handlers are executed according to bytecodes that are inturn made up of instructions for performing a variety of operations, sothat a variety of operations, such as content switching, and changes inthe display of buttons, and other operations, are possible.

Second Embodiment

[0303] The following is an explanation of the second embodiment of thepresent invention, which is a data display control apparatus thatincludes a construction for changing the operations performed inresponse to user operations according to the time such user operationsare made.

[0304] It should be noted here that the only difference with the datatransmission apparatus of the first embodiment lies in the content ofthe transmitted navigation information, so that other elements will notbe described. Instead, the following explanation will describe thepresent data display control apparatus in terms of the content of thenavigation information.

[0305] The data display control apparatus of this second embodiment hasa feature whereby it sets a valid period for each handler and, whenactivating a handler in response to a user operation, activates anoptimal handler for the time at which the user operation is made. Thisis an extension of the characteristic feature of the first embodiment ofthe present invention.

Construction

[0306] The construction of the data display control apparatus of thesecond embodiment is the same as that of the first embodiment (see FIG.7), so that the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100. The operation of the reception controlunit 1050, however, is different in the second embodiment, so that thiswill be described in more detail below.

Data Construction

[0307] Of the data handled by the data display control apparatus of thesecond embodiment, only the navigation information differs from the datadescribed in the first embodiment, with the other kinds of data beingthe same as before.

[0308] The data construction of the navigation information 2170 is shownin FIG. 17. This navigation information 2170 is an extension of thenavigation information 2160 described in the first embodiment, andincludes a Time_Event_Part 2171, a Bytecode_Part 2172, a Handler_Part2173, a Graphics_Property_Part 2174, a Bitmap_Information_Part 2175, anda Hyperlink_Information_Part 2176.

[0309] Here, the Time_Event_Part 2171 is the same as the Time_Event_Part2161 in the first embodiment, the Bytecode_Part 2172 is the same as theBytecode_Part 2162, the Graphics_Property_Part 2174 is the same as theGraphics_Property_Part 2164, the Bitmap_Information_Part 2175 is thesame as the Bitmap_Information_Part 2165, and theHyperlink_Information_Part 2176 is the same as theHyperlink_Information_Part 2166, with the only the set values beingdifferent for explanatory purposes (see FIG. 11).

[0310] The only difference with the first embodiment lies in theHandler_Part 2173 that includes valid periods which have been set foreach of the handler numbers.

[0311] For the example shown in FIG. 17, the valid sub-handler for thehandler number 0 until the time 14:59:59 on Sep. 9, 1996 is sub-handlernumber 0, while the valid sub-handler for the handler number 0 from thetime 15:00:00 on Sep. 9, 1996 onwards is sub-handler number 2. In thesame way, the valid sub-handler for the handler number 1 until the time14:59:59 on Sep. 9, 1996 is sub-handler number 1, while the validsub-handler for the handler number 1 from the time 15:00:00 on Sep. 9,1996 onwards is sub-handler number 2. Here, sub-handler number 0corresponds to bytecode number 0, while sub-handler number 1 correspondsto bytecode number 1 and sub-handler number 2 corresponds to bytecodenumber 2.

[0312] It should be noted that while this setting of a valid period hasbeen given as a starting time and ending time, a setting of only one ofthese may alternatively be used, while no setting of starting time orending time corresponds to a case when a handler is always valid.

[0313]FIG. 18 shows the data construction of navigation information 2270and FIG. 19 shows the data construction of navigation information 2370.These sets of navigation information 2270 and 2370 have the same dataconstruction as navigation information 2170 described above.

Operation of the Reception Control Unit 1050

[0314] The following is an explanation of the operation of the receptioncontrol unit 1050 in the data display control apparatus 1000 describedabove, with reference to the drawings. This operation will be describedusing contents 2100, 2200, and 2300 of FIGS. 8 and 9 described in thefirst embodiment. The difference, however, lies in the replacement ofthe navigation information 2160, 2260, and 2360 with the navigationinformation 2170, 2270, and 2370, and a difference in the transformationbetween the contents shown in FIG. 8.

[0315] The reception control unit 1050 is composed of a CPU and aprogram, and performs the processing for content switching and handleractivation. The fundamental operation is the same as in the firstembodiment (see FIG. 14), with the only difference being in theprocessing in the handler activation process of S3130. This is describedin more detail below.

[0316]FIG. 20 is a flowchart for the operation during handler activationin the second embodiment.

[0317] The handler activation process is composed of a process in S3131and S3132 for obtaining the present time, and a process in S3133 toS3137 for judging the validity of the sub-handlers, which are units ofthe handler to be activated, based on their valid periods, and foractivating valid sub-handlers.

[0318] The present explanation supposes that the present time is14:58:00 on Sep. 9, 1996 and that the user has selected and activatedthe “Video” button during a display of content 2100.

[0319] The activation process for a handler starts with the acquisitionof the present time (S3131). The reception control unit 1050 obtains theTDT and TOT from the time information storage unit 1044 and obtains thestandard time, before amending this time for the time difference of thecountry set for the data display control apparatus 1000 (S3132). Theacquisition of the present time and amendment for a time difference areperformed in the same way as in the first embodiment, and result in thetime 14:58:00 on Sep. 9, 1996 being obtained.

[0320] The reception control unit 1050 next focuses on one of thesub-handlers of the indicated handler (S3133) and judges whether thepresent time falls within the valid period of the focused sub-handler(S3134). The handler indicated here is a handler that has been selectedby a user selection operation for a button or, as in the firstembodiment, a handler that has been activated due to its indicated timehaving been reached.

[0321] In the example in FIG. 17, the button “Video” is selected so thatthe handler with the handler number “0” is activated. The receptioncontrol unit 1050 focuses on the sub-handler with the sub-handler number“0” for the handler “0” given in the Handler_Part 2173 (S3133), and,since this sub-handler is valid until 14:59:59 on Sep. 9, 1996 (S3134),executes the bytecode corresponding to the present sub-handler (S3135).As a result, the bytecode with the bytecode number “0” corresponding tothe sub-handler “0” is executed. Since the bytecode with the bytecodenumber “0” shown in the Bytecode_Part 2172 is “PushL0, GotoPage”, thecontent with “VE_id=1, NE_id=1” given in the Hyperlink_Information_Part2176 is displayed.

[0322] After the processing for the sub-handler “0” has been completed,the reception control unit 1050 judges whether there is a nextsub-handler (step 3136), and since there is another sub-handler with thesub-handler number “2”, focuses on the sub-handler with the sub-handlernumber “2” (S3137). The reception control unit 1050 then judges whetherthe present time is within the valid period of the sub-handler (S3134),and since this is not the case, skips the execution of the sub-handler.The reception control unit 1050 then finds that there are no moresub-handlers, and so completes the handler activation process.

[0323] The following is a description of the transformation of thedisplay screen in the second embodiment, with reference to FIG. 21.

[0324] Display screen transformation 3310 shows the transformation inthe screen that is displayed at 14:58:00 on Sep. 9, 1996 in the presentexample. As shown in the drawing, the displayed content switches fromcontent 2100 to content 2200 in response to a selection of the “Video”button by the user.

[0325] Next, the user selects the “Menu” button in content 2200. Sincethe handler with the handler number “0” in the Handler_Part of thenavigation information 2270 corresponding to content 2200 is set tocorrespond to sub-handler 0 without a limited valid period, and thesub-handler 0 corresponds to bytecode 0, the reception control unit 1050has the bytecode interpreter 1051 execute the bytecode 0, so thatcontent 2100 is displayed.

[0326] After this, time passes and the present time reaches 15:01:00 onSep. 9, 1996.

[0327] Here, if the user selects the “Video” button, the handleractivation process will be as described below.

[0328] First, the reception control unit 1050 obtains the present time(S3131) and amends the time using the time difference (S3132). By doingso, the time, 15:01:00 on Sep. 9, 1996 is obtained.

[0329] Next, the reception control unit 1050 focuses on the firstsub-handler for the indicated handler (S3133), and judges whether thepresent time is within the valid period (S3134). For the example shownin FIG. 17, the selection of the “Video” button results in theactivation of the handler with the handler number “0”, so that thereception control unit 1050 first focuses on the sub-handler “0”(S3133). Since this sub-handler is only valid until 14:59:00 on Sep. 9,1996, this sub-handler is judged as invalid (S3134) and so is notexecuted. The reception control unit 1050 then focuses on thesub-handler with the sub-handler number “2” (S3136, S3137) which isvalid from 15:00:00 on Sep. 9, 1996 onwards. Accordingly, the receptioncontrol unit 1050 judges that this sub-handler “2” is valid (S3134) andso executes the bytecode corresponding to the sub-handler “2” (S3135).

[0330] The bytecode with the bytecode number “2” given in theBytecode_Part 2172 is “PushL2, PushL1, SetGraphicVisibility, PushL0,PushL0, SetGraphicVisibility, PushL1, PushL0, SetGraphicVisibility”, sothat in the same way as in the first embodiment, the button “This offeris no longer valid” is made visible, and the “Video” and “Stereo”buttons are made invisible.

[0331] After executing this bytecode, there are no more sub-handlers(S3136), so that the reception control unit 1050 terminates the handleractivation process.

[0332] As a result, the display screen is transformed as shown in 3320in FIG. 21, so that the display switches from content 2100 to content2400 in response to a user selection of the “Video” button.

[0333] As described above, the data display control apparatus 1000 ofthe second embodiment of the present invention is able to handlenavigation information which has a data construction that includes validperiods for handlers, meaning that a greater variety of processes areavailable in response to time.

Third Embodiment

[0334] The following is an explanation of the data display controlapparatus of the third embodiment of the present invention. This datadisplay control apparatus receives a digital broadcast and ischaracterized by including a construction for performing certainoperations only when specified graphics are displayed at a specifictime.

[0335] The data transmission apparatus of this third embodiment differsfrom the first embodiment in only the content of the transmittednavigation information, so that the construction of the data displaycontrol apparatus has been omitted. Instead, the data display controlapparatus of this third embodiment will be described in terms of thecontent of the navigation information.

[0336] The data display control apparatus of this third embodiment has afunction for only performing certain operations when specified graphicsare displayed, in addition to the function of the first embodimentwhereby an specified operation is performed at an indicated time.

Construction

[0337] The construction of the data display control apparatus of thethird embodiment is the same as that of the first embodiment (see FIG.7), so that the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100. The operation of the reception controlunit 1050, however, is different in the third embodiment, so that thiswill be described in more detail below.

Data Construction

[0338] Of the data handled by the data display control apparatus of thethird embodiment, only the navigation information differs from the datadescribed in the first embodiment, with the other kinds of data beingthe same as before.

[0339] The data construction of the navigation information 2180 is shownin FIG. 22. This navigation information 2180 is an extension of thenavigation information 2160 described in the first embodiment, andincludes a Time_Event_Part 2181, a Bytecode_Part 2182, a Handler_Part2183, a Graphics_Property_Part 2184, a Bitmap_Information_Part 2185, anda Hyperlink_Information_Part 2186.

[0340] Here, the Bytecode_Part 2182 is the same as the Bytecode_Part2162 in the first embodiment, the Handler_Part 2183 is the same as theHandler_Part 2163, the Graphics_Property_Part 2184 is the same as theGraphics_Property_Part 2164, the Bitmap_Information_Part 2185 is thesame as the Bitmap_Information_Part 2165, and theHyperlink_Information_Part 2186 is the same as theHyperlink_Information_Part 2166 (see FIG. 11).

[0341] The only difference with the first embodiment lies in theTime_Event_Part 2181 which, in addition to the activate times andhandler numbers of the Time_Event_Part 2161 of the first embodiment,contains graphic numbers.

[0342] For the example shown in FIG. 22, the Time_Event_Part 2181 showsthat if the present time reaches 15:00:00 on Sep. 9, 1996 and thegraphics with the graphics numbers “0” and “1” are being visiblydisplayed, the processing with the handler number “2” will be performed.

Operation Control Construction

[0343] The following is an explanation of the operation of the receptioncontrol unit 1050. Here, the flowchart in FIG. 23 shows the contentswitching process and activation of a handler. With the exception of theprovision of step S5101 corresponding to the Time_Event_Part 2181 in thenavigation information, this flowchart is the same as FIG. 14 whichshowed the operation of the reception control unit 1050 in the firstembodiment. Accordingly, only S5101 will be described.

[0344] Step S5101 is a process performed as a branch from step S5100when the activate time of 15:00:00 on Sep. 9, 1996 in theTime_Event_Part 2181 has been reached. Here, the reception control unit1050 judges whether the graphics with the graphics numbers “0” and “1”given in the Time_Event_Part 2181 are being displayed and, if so,executes the handler activation process (S5130). When these graphics arenot being displayed, the reception control unit 1050 performs theprocessing for the movement of the selection pointer in accordance withuser inputs (S5110).

[0345] As a result, when graphics “0” and “1” are being displayed andthe present time reaches 15:00:00 on Sep. 9, 1996, the reception controlunit 1050 activates the handler with the handler number “2”.

[0346] Here, by providing navigation information and an receptioncontrol unit which controls the display of data by referring to thenavigation information, it becomes possible to achieve control oftime-based operations in accordance with the graphics that are beingdisplayed. Developers of programs are thereby able to produce programswhere the state of the displayed graphics changes according to useroperations, allowing the display to be controlled more precisely.

Fourth Embodiment

[0347] The following is an explanation of the data display controlapparatus of the fourth embodiment of the present invention. This datadisplay control apparatus receives a digital broadcast and ischaracterized by including a construction for performing control todisplay or not display graphics at a specific time.

[0348] The data transmission apparatus of this fourth embodiment differsfrom the first embodiment in only the content of the transmittednavigation information, so that the construction of the data displaycontrol apparatus has been omitted. Instead, the data display controlapparatus of this fourth embodiment will be described in terms of thecontent of the navigation information.

Construction

[0349] The construction of the data display control apparatus of thefourth embodiment is the same as that of the first embodiment (see FIG.7), so that the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100. The operation of the reception controlunit 1050, however, is different in this fourth embodiment, so that thiswill be described in more detail below.

Data Construction

[0350] Of the data handled by the data display control apparatus of thefourth embodiment, only the navigation information differs from the datadescribed in the first embodiment, with the other kinds of data beingthe same as before.

[0351] The data construction of the navigation information 6160 is shownin FIG. 24. This navigation information 6160 corresponds to thenavigation information 2160 described in the first embodiment, andincludes a Bytecode_Part 6162, a Handler_Part 6163, aGraphics_Property_Part 6164, a Bitmap_Information_Part 6165, and aHyperlink_Information_Part 6166.

[0352] Here, the Bytecode_Part 6162 is the same as the Bytecode_Part2162 in the first embodiment, the Handler_Part 6163 is the same as theHandler_Part 2163, the Bitmap_Information_Part 6165 is the same as theBitmap_Information_Part 2165, and the Hyperlink_Information_Part 6166 isthe same as the Hyperlink_Information_Part 2166 (see FIG. 11).

[0353] The differences with the first embodiment lie in the lack of aTime_Event_Part in the present embodiment, and in the construction ofthe Graphics_Property_Part.

[0354] In addition to the graphics numbers, graphics types, coordinates,handler numbers, and initial states of the Graphics_Property_Part 2164of the first embodiment, the Graphics_Property_Part 6164 additionallyincludes information for a pairing of a time and display state. Notehere that it is also possible for a plurality of pairings of a time anddisplay state to be given in this Graphics_Property_Part.

[0355] For the example shown in FIG. 24, the Graphics_Property_Part 6164includes a time and a display state for each of graphics numbers 0, 1,and 2, so that the button with the graphics number 0 and the button withthe graphics number 1 are made invisible at 15:00:00 on Sep. 9, 1996,while the button with the graphics number 2 is made visible at 15:00:00on Sep. 9, 1996.

Operation Control Construction

[0356] The following is an explanation of the operation of the receptioncontrol unit 1050 based on the example data shown in FIG. 24. Here,operations which are the same as those described in the first embodimenthave been omitted.

[0357]FIG. 25 is a flowchart showing the content switching process andthe process for activation of a handler in the present fourthembodiment. FIG. 26 shows the transformation in the display screen inthis fourth embodiment.

[0358] The reception control unit 1050 first displays the first contentgiven as the information designated by the VE_id and the NE_id given inthe PMT in the system information storage unit 1043 (S6510). Thefollowing explanation will deal with the case when “VE_id=0” and“NE_id=0” is given in the PMT. The explanation also supposes that thepresent time is 14:59:00 on Sep. 9, 1996.

[0359] The reception control unit 1050 obtains the present time andadjusts it using the time difference (S6520, S6530). Here, since theGraphics_Property_Part 6164 states that the graphics for “Video” withthe graphics number “0” have an initial state of “visible” but should beinvisible after 15:00:00 on Sep. 9, 1996, the reception control unit1050 judges that these graphics should be visible at the present time of14:59:00 on Sep. 9, 1996 (S6540, S6550), and so makes these graphicsvisible (S6560). Next, the reception control unit 1050 focuses on thegraphics “Stereo” with the graphics number “1” (S6580, S6540), judgesthat these graphics should also be made visible (S6550), and so makesthese graphics visible (S6560). Next, the reception control unit 1050focuses on the graphics “This offer is no longer valid” with thegraphics number “2” (S6580, S6540), but since these graphics should onlybe made visible after 15:00:00 on Sep. 9, 1996, judges that thesegraphics should be invisible at the present time of 14:59:00 on Sep. 9,1996 (S6550), and so makes these graphics invisible (S6570). Thisdisplay state is shown as 6810 in FIG. 26.

[0360] On completing the graphics display processing, the receptioncontrol unit 1050 moves the selection pointer in accordance with theuser inputs (S6590), and, when there has been a button selection andactivation operation by the user (S6600), activates the handlercorresponding to the selected button (S6610).

[0361] Hereafter, time passes and the present time becomes 15:00:00 onSep. 9, 1996.

[0362] The reception control unit 1050 obtains the present time andadjusts it using the time difference (S6520, S6530). Here, since theGraphics_Property_Part 6164 states that the graphics for “Video” withthe graphics number “0” have an initial state of “visible” but should beinvisible after 15:00:00 on Sep. 9, 1996, the reception control unit1050 judges that these graphics should be made invisible at the presenttime of 15:00:00 on Sep. 9, 1996 (S6540, S6550), and so makes thesegraphics invisible (S6570). Next, the reception control unit 1050focuses on the graphics “Stereo” with the graphics number “1” (S6580,S6540), judges that these graphics should also be made invisible(S6550), and so makes these graphics invisible (S6570). After this, thereception control unit 1050 focuses on the graphics “This offer is nolonger valid” with the graphics number “2” (S6580, S6540). Since theGraphics_Property_Part 6164 states that these graphics have an initialstate of “invisible” but should be visible after 15:00:00 on Sep. 9,1996, the reception control unit 1050 judges that these graphics shouldbe made visible at the present time of 15:00:00 on Sep. 9, 1996 (S6550),and so makes these graphics visible (S6560).

[0363] As a result of the operation described above, the display screenbecomes as shown as 6820 in FIG. 26.

[0364] With the data display control apparatus of the presentembodiment, control can be performed to display or not display graphicsat a time which is indicated separately for each set of graphics.

Fifth Embodiment

[0365] The following is an explanation of the data display controlapparatus of the fifth embodiment of the present invention. This datadisplay control apparatus receives a digital broadcast and ischaracterized by including a construction for adjusting the startingtimes of programs and starting programs once a specified time has beenreached.

[0366] The data transmission apparatus of this fifth embodiment differsfrom the first embodiment in only the content of the transmittednavigation information, so that the construction of the data displaycontrol apparatus has been omitted. Instead, the data display controlapparatus of this fifth embodiment will be described in terms of thecontent of the navigation information.

Construction

[0367] The construction of the data display control apparatus of thefifth embodiment is the same as that of the first embodiment (see FIG.7), so that the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100. The operation of the reception controlunit 1050, however, is different in this fifth embodiment, so that thiswill be described in more detail below.

Data Construction

[0368] Of the data handled by the data display control apparatus of thefifth embodiment, only the navigation information differs from the datadescribed in the first embodiment, with the other kinds of data beingthe same as before.

[0369] The data construction of the navigation information 7160 is shownin FIG. 27. This navigation information 7160 corresponds to thenavigation information 2160 described in the first embodiment, andincludes a Time_Event_Part 7161, a Bytecode_Part 7162, a Handler_Part7163, a Graphics_Property_Part 7164, a Bitmap_Information_Part 7165, anda Hyperlink_Information_Part 7166.

[0370] Here, the Time_Event_Part 7161 is the same as the Time_Event_Part2161 in the first embodiment, the Bytecode_Part 7162 is the same as theBytecode_Part 2162, the Handler_Part 7163 is the same as theHandler_Part 2163, the Graphics_Property_Part 7164 is the same as theGraphics_Property_Part 2164, the Bitmap_Information_Part 7165 is thesame as the Bitmap_Information_Part 2165, and theHyperlink_Information_Part 7166 is the same as theHyperlink_Information_Part 2166 (see FIG. 11).

[0371] The difference with the data construction of the first embodimentlies in the inclusion of an NE start time in addition to the NE_id ineach navigation element.

[0372] For the example in FIG. 27, the NE start time shows thatexecution can only be performed from 14:00:00 on Sep. 9, 1996 onwards,so that even if there is a user operation which selects the contentcorresponding to the navigation element with the NE_id “0” before14:00:00 on Sep. 9, 1996, the data display control apparatus will waituntil the present time reaches 14:00:00 on Sep. 9, 1996 before referringto the navigation element with this NE_id “0” and performing the controlof the display.

Operation Control Construction

[0373] The following is an explanation of the operation of the receptioncontrol unit 1050 based on the example data shown in FIG. 27. Here,operations which are the same as those described in the first embodimenthave been omitted.

[0374]FIG. 28 is a flowchart showing the content switching process andthe process for activation of a handler in the present fifth embodiment.

[0375] This explanation supposes that the present time is 13:59:00 onSep. 9, 1996, and that the user has made a selection and activationoperation for a button which switches from a given content to a contentidentified by NE_id=0 and VE_id=0.

[0376] The reception control unit 1050 judges that there has been acontent switching (S7510), obtains the present time, and adjusts thepresent time using the time difference (S7520, S7530).

[0377] After this, the reception control unit 1050 refers to thenavigation element with the NE_id=0, finds that the NE start time isgiven as 14:00:00 on Sep. 9, 1996, obtains the present time once again,and performs adjustment for the time difference (S7540, S7520, andS7530).

[0378] Here, time passes and the processing in steps S7540, 7520, andS7530 are repeated until the present time is judged to have reached14:00:00 on Sep. 9, 1996 (S7540), at which point the content isdisplayed (S7550).

[0379] The following processes (S7560-S7650) are the same as S3040-S3130in the first embodiment, and so will not be described.

[0380] By operating in this way, the reception control unit 1050 candisplay contents only after an indicated time has been reached, so thata digital broadcasting system can perform control in accordance with theprogression of programs while maintaining their interactive aspects.

Sixth Embodiment

[0381] The following is an explanation of the data display controlapparatus of the sixth embodiment of the present invention. This datadisplay control apparatus receives a digital broadcast and ischaracterized by including a construction for performing control toexecute a specified operation once a predetermined time period haselapsed from the start of display of a content.

[0382] The data transmission apparatus of this sixth embodiment differsfrom the first embodiment in only the content of the transmittednavigation information, so that the construction of the data displaycontrol apparatus has been omitted. Instead, the data display controlapparatus of this sixth embodiment will be described in terms of thecontent of the navigation information.

Construction

[0383] The construction of the data display control apparatus of thesixth embodiment is the same as that of the first embodiment (see FIG.7), so that the data display control apparatus 1000 is composed of areception unit 1010, a TS decoder unit 1020, an AV decoder unit 1030, areceived data storage unit 1040, a reception control unit 1050, areproduction unit 1060, a display unit 1070, an audio output unit 1080,and a signal reception unit 1100.

[0384] The time information storage unit 1044 in the received datastorage unit 1040 differs to the first embodiment in that the presenttime is stored by a counting unit (not illustrated) provided in the datadisplay control apparatus. The present time calculated by this countingunit is expressed as hours, minutes, seconds, and frames, such as 11hours, twenty minutes, 30 seconds and 15 frames, where one frame is onethirtieth of one second. Here, however, one frame may be set as onetwenty-fifth of one second, so that the term “frame” simply represents apredetermined unit of time.

[0385] The operation of the reception control unit 1050 differs to thatin the first embodiment, with this being described in more detail below.

Display Screens and Data Composing Contents

[0386] The following is an explanation of the display of contents by thedata display control apparatus 1000 and of the data composing contents,with reference to FIGS. 29, 30, and 31.

[0387]FIG. 29 shows example display screens for the data display controlapparatus 1000 of the sixth embodiment of the present invention. Thesedisplay screens relate to a quiz program, and include a content 8100displaying a question, a content 8200 displaying indicating that acorrect answer has been given, a content 8300 displaying indicating thatan incorrect answer has been given, and a content 8400 displaying thattime is up.

[0388] In this example, when the content 8100 for the question “Which isa red fruit ?” is displayed on the display screen and the user selectsand confirms the “Apple” button 8110, the display screen switches, asshown by the arrow 8010, to a display of the content 8200 showing thatthe correct answer has been given. In the same way, when the userselects and confirms the “Tangerine” button 8120, the display screenswitches, as shown by the arrow 8020, to a display of the content 8300showing that an incorrect answer has been given.

[0389] When ten seconds have passed from the start of the display ofcontent 8100, the display switches to content 8400 showing that time isup.

Data Transmission Apparatus

[0390] To allow the data display control apparatus of the sixthembodiment of the present invention to perform the switching of displayin response to interactive operations, data composing the contents istransmitted as described below.

[0391] It should be noted that the data transmission apparatus of thesixth embodiment has the same construction as the data transmissionapparatus 101 described in the related art section. As described below,however, unlike the navigation information of the related art, thenavigation information of the present embodiment includes information toallow control with a time element.

[0392]FIG. 30 gives a simplified representation of the data transmittedby the data transmission apparatus. FIG. 30 shows the data that composesthe contents shown in FIG. 29, with the data 8000 being transmitted witha predetermined period by the data transmission apparatus. Thistransmitted data 8000 is composed of the sets of image data 8150, 8250,8350, and 8450, and the sets of navigation information 8160, 8260, 8360,and 8460.

[0393] These sets of image data 8150, 8250, 8350, and 8450 are thebackground images for the contents 8100, 8200, 8300, and 8400 which aredisplayed on the display screen of the data display control apparatus1000.

[0394] The data transmission apparatus repeatedly multiplexes andtransmits the data 8000 with a predetermined interval, with thistransmission being the same as shown in FIG. 4 of the related artsection, except that the image data and navigation information in FIG. 4are replaced with those shown in FIG. 30. The multiplexing is alsoperformed in the same manner as shown in FIG. 5 of the related artsection.

Detailed Description of the Navigation Information

[0395] The following is a description of the navigation informationshown in outline in FIG. 30, with reference to FIG. 31.

[0396]FIG. 31 shows the data construction of the navigation information8160. This navigation information is composed of a Time_Event_Part 8161,a Bytecode_Part 8162, a Handler_Part 8163, a Graphics_Property_Part8164, a Bitmap_Information_Part 8165, and a Hyperlink_Information_Part8166.

[0397] The data construction of the navigation information 8160 islargely the same as the data construction of the navigation information2160 in the first embodiment, although there are differences in theTime_Event_Part 8161.

[0398] The Time_Event_Part 8161 corresponds to the information shown as“Time_Event” in FIG. 30, and is used to record information foractivating a specified handler when an indicated time has elapsed fromthe start of display of the content. In the example of FIG. 31, thehandler with the handler number “2” is activated ten seconds from thestart of display of the content. Here, it is possible for a plurality ofelapsed times before activation to be recorded in the Time_Event_Part.These elapsed times are given in hour, minute, second, and frame format.

[0399] The Bytecode_Part 8162 is used to record the bytecodes. In theexample of FIG. 31, the bytecode with the bytecode number “0” is“PushL0, GotoPage” expressing a switch of display to a content shown bylink number “0”, the bytecode with the bytecode number “1” is “PushL1,GotoPage” expressing a switch of display to a content shown by linknumber “1”, and the bytecode with the bytecode number “2” is “PushL2,GotoPage” expressing a switch of display to a content shown by linknumber “2”.

[0400] The Bitmap_Information_Part 8165 records the contents of thebitmaps used to display the buttons corresponding to different graphicsnumbers. In the example in FIG. 31, the graphics number “0” correspondsto the bitmap for “Apple” and the graphics number “1” corresponds to thebitmap for “Tangerine”.

[0401] The Graphics_Property_Part 8164 is information for composing theon-screen display graphics. In the example in FIG. 31, the graphics typeis “Button”, the graphics numbers “0” and “1” correspond to the numbersof the graphics included in the Bitmap_Information_Part, and thecoordinates of button “0” and button “1” are given as (20,20) and(20,60). The handlers which are activated when button “0” and button “1”are selected are given as handler numbers “0” and “1”, and the initialstates of the buttons for the display of the contents are both given as“visible”.

[0402] The Hyperlink_Information_Part 8166 records the IDs of thematerials that compose the link destination contents, and has acollection of identifiers corresponding to each content that isidentified as a link number. For the example in FIG. 31, “VE_id=1” isgiven as the link destination for link “0”, and so shows that thecontent composed of the image data with the VE_id “1” is a linkdestination. The link destination for the link number “1” is shown asthe content composed of the image data with the VE_id=2, and the linkdestination for the link number “2” is shown as the content composed ofthe image data with the VE_id=3.

[0403] It should be noted here that NE_id given as “0” at the top ofFIG. 31 shows that the navigation information being explained here isthe navigation element which has the ID The navigation information withthis “NE_id=0” forms a content together with the image data fordisplaying the question that has the VE_id “0”.

[0404] Using the data described above, a new content will be displayedwhen a user makes a button operation in response to a content displayedby the data display control apparatus 1000. Also, when the time periodgiven in the Time_Event_Part has elapsed from the start of display of acontent, control is performed to execute the specified operation.

Operation of the Data Display Control Apparatus

[0405] The following is a description of the operation of the receptioncontrol unit 1050 of the data display control apparatus 1000 based onthe data construction described above, with reference to the drawings.

[0406]FIG. 32 is a flowchart showing the content switching process andactivation of a handler, while FIGS. 33A and 33B show the transformationin the display screen when the user gives an answer within the setresponse time, and when the user does not give an answer within the setresponse time.

[0407] The processing of the reception control unit 1050 is composed ofsteps S8510 to S8620 in FIG. 32. Step S8510 is an initial process forindicating the content to be displayed first when the reception of aprogram is commenced. When S8520 judges that content switching has beenperformed, steps S8530 to S8560 are performed. When S8570 judges thatthere is a handler to be executed at an indicated time, the processes inS8580 and S8590 are performed. Steps S8600 and S8610 are performed inresponse to user inputs and step S8620 is performed to activate ahandler.

[0408] The information specifying the first content is given as a pairof a VE_id and an NE_id in the PMT stored in the system informationstorage unit 1043. In the following explanation, an example where theinformation “VE_id=0” and “NE_id=0” is given in the PMT is used.

[0409] First, the reception control unit 1050 obtains the information“VE_id=0”, “NE_id=0” from the PMT as the information for the content tobe displayed first (S8510).

[0410] Since this is the first content, the system considers thatcontent switching has been performed (S8520:Yes) and so displays thepresent content (S8530).

[0411] The display of this first content is achieved by displaying theimage data 8150 with the VE_id=0 as the background image and on-screendisplay graphics in accordance with the content of the navigationinformation with the NE_id=0. Here, the button “Apple” is visiblydisplayed at a position given by the coordinates (20,20) and the button“Tangerine” is visibly displayed at a position given by the coordinates(20,60), in accordance with the content of the Graphics_Property_Part8164 and the Bitmap_Information_Part 8165 of the navigation informationshown in FIG. 31. This results in the display shown as 8910 in FIG. 33A.

[0412] Once the present content has been displayed, the receptioncontrol unit 1050 judges whether there is a time period indication forthe activation of a handler at a specified period after the start ofdisplay in the Time_Event_Part of the NE (S8540), in which case the timeperiod indication flag for handler activation processing in response totime is set at “1” (S8550). When there is no time period indication, thetime period indication flag is set at “0” (S8560). Here, since thehandler with the handler number “2” in the Time_Event_Part of thenavigation information shown in FIG. 31 is set as being activated at apoint where ten seconds have elapsed from the start of display, the timeperiod indication flag is set at “1” (S8550).

[0413] When the time period indication flag has been set at “1”(S8570:Yes), the reception control unit 1050 measures the elapsed timefrom the start of display of the content (S8580) and judges whether theelapsed time has reached the time period indicated for the activation ofthe handler in the Time_Event_Part 8161 of the NE (S8590). When theindicated period has not elapsed, the reception control unit 1050switches to the processing for the movement of the selection pointer inaccordance with user operations (S8600). When one of the buttons hasbeen selected and activated (S8610), the reception control unit 1050advances to the handler activation step (S8620).

[0414] The case where the user gives his/her response five seconds fromthe start of display of the question is described below.

[0415] Since ten seconds have not elapsed (S8580, S8590), the receptioncontrol unit 1050 proceeds to the processing for the movement of theselection pointer in accordance with user operations (S8600). When theuser selects and activates the button “Apple” five seconds from thestart of the display of the content (S8610), the reception control unit1050 refers to the Graphics_Property_Part 8164 and activates the handlerwith the handler number “0” (S8620). The handler with the handler number“0” is composed of the bytecode “0” whose content is “PushL0, GotoPage”,so that content switching is performed to the content with the VE=id “1”for the link number “0” given in the Hyperlink_Information_Part 8166.This execution of bytecodes is performed by the bytecode interpreter1051 of the reception control unit 1050.

[0416] After activation of a handler (S8620), the reception control unit1050 returns to S8520 to judge that content switching has been performedand so display the new content (S8530). This results in the displayscreen for a correct answer being displayed, as shown by display 8920 inFIG. 33A.

[0417] The case where the user does not gives his/her response withinten seconds from the start of display of the question is describedbelow. Note that the display at the start of this procedure is display8930 of FIG. 33B.

[0418] Once ten seconds have elapsed from the start of display (S8580,S8590), the handler with the handler number “2” is activated (S8620).The handler with the handler number “2” is composed of the bytecode “2”whose content is “PushL2, GotoPage”, so that content switching isperformed to the content with the VE=id “3” for the link number “2”given in the Hyperlink_Information_Part 8166.

[0419] After activation of a handler (S8620), the reception control unit1050 returns to S8520 to judge that content switching has been performed(S8520) and so display the new content (S8530). This results in thedisplay screen for “time up” being displayed, as shown by display 8940in FIG. 33B.

[0420] By operating in this way, the data display control apparatus 1000can execute the processing of a specified handler after a predeterminedtime period has elapsed starting from the display of a content by thedata display control apparatus 1000.

Seventh Embodiment

[0421] The following is an explanation of the seventh embodiment of thepresent invention, with reference to the drawings. The presentembodiment relates to a data display control information editingapparatus which displays the interrelations of contents at a timeindicated by the user.

Construction

[0422] The construction of the data display control information editingapparatus of the seventh embodiment is shown by the block diagram inFIG. 34.

[0423] The data display control information editing apparatus 10000 iscomposed of a time input receiving unit 10010, a data storage unit10020, a content relation judging unit 10030, and a content relationdisplay unit 10040.

[0424] The time input receiving unit 10010 receives a user input of astandard time for displaying the interrelations of contents. Here, adirect numerical input of time made by the user is stored in an internalregister (not illustrated).

[0425] The data storage unit 10020 stores the navigation information.The data construction of this navigation information is the same as thatdescribed in the second embodiment (see FIG. 17).

[0426] The content relation judging unit 10030 refers to theHandler_Part , the Bytecode_Part , and the Hyperlink_Information_Part ofthe navigation information stored in the data storage unit 10020, and,by investigating the contents of the bytecodes corresponding to thevalid sub-handlers at the indicated time obtained by the time inputreceiving unit 10010, outputs the NE_id and VE_id of the contents thatare link destinations for the sub-handlers that are valid at theindicated time to registers (not illustrated) provided in the datadisplay control information editing apparatus.

[0427] The content relation display unit 10040 displays imagesrepresenting the contents and lines representing the links betweencontents on a display screen.

Operation

[0428] The following is a description of a specific example of theoperation of the data display control information editing apparatus10000 based on the example sets of navigation information shown in FIGS.17 to 19. A flowchart for the operation of the data display controlinformation editing apparatus 10000 is shown in FIG. 35.

[0429] The content relation display unit 10040 first refers to theHandler_Part, the Bytecode_Part, and the Hyperlink_Information_Part ofthe navigation information stored in the data storage unit 10020 andinvestigates the contents of the bytecodes corresponding to all of thesub-handlers. As a result, “GotoPage” is detected, and the NE_id andVE_id of all of the link destination contents are obtained (S10110,S10120, S10130). The content relation display unit 10040 then displaysthe link relations of contents by displaying images for the contents andlines representing the links between the contents (S10140, S10150).Here, however, the lines between contents are drawn as broken linesshowing that the links are invalid. Icons are used in the display as theimages for representing contents and each record the VE_id and NE_id ofthe elements which compose the content represented by the icon.

[0430]FIG. 36 shows an example of a display screen displayed by the datadisplay control information editing apparatus 10000.

[0431] After step S10150 has been completed, the display screen is asshown by display 10300 in FIG. 36.

[0432] The time input receiving unit 10010 next receives an user inputof an indicated time (S10160), which in the present example is 14:59:00on Sep. 9, 1996.

[0433] The content relation judging unit 10030 first refers to theHandler_Part 2173 of the navigation information 2170 with the NE_id=0,and judges that the sub-handler “0” is valid at 14:59:00 on Sep. 9, 1996(S10170, S10180). The content relation judging unit 10030 then detectsthe bytecode “PushL0, GotoPage” corresponding to the sub-handler “0”that executes a link to the content with the link number “0”, and sosets the link to the content given by the NE_id=1, VE_id=1 for the linknumber “0” as valid, storing the values NE_id=1, VE_id=1 in an internalregister (S10190).

[0434] Following this, the content relation judging unit 10030 focuseson the sub-handlers “1” and “2” of the navigation information 2170,before focusing on the sub-handler “0” of the navigation information2270 and the sub-handler “0” of the navigation information 2370, andexecuting the same processing as described above (S10170, S10180,S10190, and S10200).

[0435] As a result, the content relation display unit 10040 draws solidlines showing the valid links between contents based on the informationfor links which are valid at the indicated time 14:59:00 on Sep. 9, 1996(S10210). This results in the display shown as display 10400 in FIG. 36.

[0436] As described above, the data display control information editingapparatus of the seventh embodiment is able to display the links betweencontents at a time indicated by the user in a way which allows the userto distinguish valid links from invalid links.

Eighth Embodiment

[0437] The following is a description of the eighth embodiment of thepresent invention, with reference to the drawings.

[0438] In addition to the functions of the seventh embodiment, the datadisplay control information editing apparatus of the eighth embodimentis able to update the information for controlling the display of data.

Construction

[0439]FIG. 37 is a block diagram showing the construction of the datadisplay control information editing apparatus of the eighth embodimentof the present invention.

[0440] The data display control information editing apparatus 10500 iscomposed of a time input receiving unit 10010, a data storage unit10020, a content relation judging unit 10030, a content relation displayunit 10040, a non-link destination content selection receiving unit10510 and a data updating unit 10520.

[0441] The time input receiving unit 10010, the data storage unit 10020,the content relation judging unit 10030, and the content relationdisplay unit 10040 are the same as in the seventh embodiment, and sowill not be explained further.

[0442] The non-link destination content selection receiving unit 10510has the user select a content to which a link is to be prohibited, andoutputs the VE_id and NE_id of the selected content to a registerprovided in the data display control information editing apparatus. Thisuser selection of a content can be made, for example, by indicating oneof the icons representing contents on the content relation display unit10040 using a selection pointer.

[0443] The data updating unit 10520 updates the content of the datastorage unit 10020 by resetting the valid period information for thesub-handler corresponding to the bytecode which represents the link tothe content selected by the non-link destination content selectionreceiving unit 10510, based on the indicated time received by the timeinput receiving unit 10010.

[0444] As a result, the data updating unit 10520 resets the navigationinformation so that a sub-handler representing a link to the selectedcontent will be made invalid from the indicated time onwards.

Operation

[0445] The following is an explanation of the operation of the datadisplay control information editing apparatus 10500 for the samespecific data example as the seventh embodiment, with reference to FIGS.36, 38, and 39.

[0446]FIG. 38 is a flowchart showing the operation of the data displaycontrol information editing apparatus 10500 of the eighth embodiment.

[0447] The steps in the flowchart in FIG. 38 which are the same as stepsin the flowchart for the data display control information editingapparatus 10000 of the seventh embodiment have been given the samereference numerals and will not be explained. The following explanationwill instead focus on the processes in S10610 onwards, and supposes thatthe display screen is as shown by display 10400 in FIG. 36.

[0448] When the user selects icon 10420 representing a content, thenon-link destination content selection receiving unit 10510 receivesthis selection and stores the NE_id and VE_id of the selected content ina register in the data display control information editing apparatus(S10610). After a selection has been received by the non-linkdestination content selection receiving unit 10510, the data updatingunit 10520 refers to the Handler_Part, the Bytecode_Part, andHyperlink_Information_Part of the navigation information in the datastorage unit 10020 based on the NE_id and VE_id in the register, anddetects the sub-handler corresponding to the switching to the contentselected by the user (S10620). The data updating unit 10520 then updatesthe ending time of the valid period of the detected sub-handler to theindicated time which was received by the time input receiving unit 10010(S10630).

[0449] When the user has selected the content with the NE_id=1 and theVE_id=1, the data updating unit 10520 refers to theHyperlink_Information_Part 2176 of the navigation information 2170, andjudges that the link with the link number “0” needs to be invalidated.The data updating unit 10520 then refers to the Bytecode_Part 2172 andthe Handler_Part 2173, detects the sub-handler “0” which corresponds tothe bytecode “0” which describes the link to the link number “0”, andresets the valid period of sub-handler handler “0” so that it ends at14:59:00 on Sep. 9, 1996.

[0450] It should be noted that while the flowchart in FIG. 38 only showsthe processing as far as the updating of the valid period of asub-handler (S10630), it is also possible for the processing to returnto S10170 or to S10160 after the completion of S10630, so as to repeatthe processing. By doing so, the user is then able to select anothercontent so that the navigation information can be updated to invalidatethe link to this content from the indicated time onwards.

[0451] As described above, the data display control information editingapparatus of the eighth embodiment updates the navigation informationbased on the selection of a content by the user and an indication oftime made by the user, so that the link to the selected content becomesinvalid at the indicated time.

[0452] The above first to eighth embodiments have been used to describethe data display control apparatus and data display control informationediting apparatus of the present invention, although it should be clearthat the present invention is not limited to these embodiments. Possiblemodifications are described below.

[0453] (1) In the first to sixth embodiments, sets of instructions aregiven as bytecodes, although a variety of instructions for a variety ofprocesses may be used as the bytecodes. As one example, instructionsrelated to hardware operations, such as powering down the system, may beused.

[0454] (2) In the first to sixth embodiments, information relating totime is set in units of one set of information for each handler,sub-handler, or set of graphics, although the same time information maybe collectively set for a plurality of handlers, sub-handlers, and setsof graphics.

[0455] (3) In the first to sixth embodiments, the contents weredescribed as being composed of combinations of still images andon-screen display graphics, although contents may include video data andaudio data. This video data and audio data may be multiplexed andtransmitted by the data transmission apparatus according to MPEG2 systemstandard.

[0456] (4) In the first to sixth embodiments, the navigation informationwas described as including a Graphics_Property_Part for indicatinggraphics, although the navigation information may also include anAudio_Property_Part that describes audio used as background music. Basedon the Audio_Property_Part, the data display control apparatus may addaudio to the display of contents. In such a case, information for thetime at which audio reproduction is valid can be given as an element ofthe Audio_Property_Part, so that the control of audio reproduction canbe achieved based on an indicated time.

[0457] (5) The first and third embodiments describe an example where ahandler is activated once an indicated time is reached, although ahandler written in a Time_Event_Part of the navigation information of anew content may also be executed when content switching is performed ifthe display time written in the Time_Event_Part has already passed.Here, a plurality of pairings of times and handler numbers may be givenin the Time_Event_Part. This may also be the same for the display ofgraphics in the fourth embodiment, so that when the indicated time haspassed, the graphics may be changed to the display state correspondingto the indicated time.

[0458] (6) The acquisition of the present time by the data displaycontrol apparatuses of the first to fifth embodiments was described asthe reception of transmitted data that expresses the present time,although each data display control apparatus may be provided with atimer mechanism from which the data display control apparatus can obtainthe present time. It should be noted here that the correction for a timedifference in such case will be a correction of the difference betweenthe standard time given in the transmitted navigation information andthe standard time of the present time obtained by the data displaycontrol apparatus from the timer mechanism.

[0459] (7) The control based on time in the second to fifth embodimentsmay be control according to an elapsed time based on a certain standardtiming, in the same way as the sixth embodiment where control isperformed according to elapsed time measured from the start of displayof a content.

[0460] (8) The first to fifth, seventh, and eighth embodiments weredescribed as handling expressions of time given in year, month, day,hour, minute, and second format, although they may instead handleexpressions of time in year format, year and month format, year, monthand day format, year, month day, and hour format, year, month, day, hourand minute format, or in a format that uses units that are smaller thanone second.

[0461] (9) The first to sixth embodiments describe the case where aVE_id is given as an element in the Hyperlink_Information_Part, althougha combination of a PID and a stream_id may be used instead of the VE_id.When doing so, when content switching is indicated by a user operation,the data display control apparatus 1000 may set the appropriate PID andother information in the filter condition storage unit 1021 and so havethe image data separated from the transmitted transport stream.

[0462] (10) In the sixth embodiment, the measuring of the elapsed timewas achieved by a timer provided in the data display control apparatus,although it is also possible for the data display control apparatus tokeep time by receiving present time information in the same way as inthe first to fifth embodiments. When doing so, the data transmissionapparatus will transmit present time information in the same way as inthe first to fifth embodiments.

[0463] (11) In the first to eighth embodiments, the input method forreceiving user operations may be achieved using a remote controller, amouse, or any other kind of input device.

[0464] (12) In the seventh and eighth embodiments, the user input of thetime indication is described as a direct input of time made using akeyboard, although an indirect input may be made by having the userselect one of a plurality of potential values displayed on the displayscreen.

[0465] (13) In the seventh and eighth embodiments, the links betweencontents were described as being represented by broken lines and solidlines drawn between contents, although other forms of representation maybe used. As one example, links that are not valid at the indicated timemay be drawn using transparent lines, which is to say the contents maybe displayed as not being linked. Any kind of image may also be used asthe icons for displaying the contents. The icons used for displayinglink destination contents may also be displayed in a manner thatdistinguishes between link destinations which are valid at the indicatedtime and link destinations which are not valid.

[0466] (14) In the seventh and eighth embodiments, the interrelationsbetween contents were displayed based on a detection of links performedby bytecodes that are “GotoPage”, although it is also possible todisplay the interrelations of the display states of contents bydetecting instructions that change display states, such as“SetGraphicVisibility” instructions.

[0467] (15) In the eighth embodiment, the valid period of a sub-handlerthat corresponds to a bytecode which achieves a link to the contentindicated by the user is updated, although it is also possible for thetime of the control for a change in the display state of graphicscorresponding to the sub-handler to be changed, so that the displaystate becomes “invisible” at a certain time. Here, however, a datastorage unit 10020 for storing the navigation information with the dataconstruction shown in the fourth embodiment becomes necessary.

[0468] (16) In the seventh and eighth embodiments, the data displaycontrol information editing apparatus displays the interrelationsbetween contents at a time indicated by the user, with the navigationinformation showing the states of contents at the indicated time beingthe same as the navigation information described in the firstembodiment. However, this display of the interrelations between contentsmay be performed using the same navigation information as in any of thesecond to fifth embodiments.

[0469] (17) The processing of the reception control unit 1050 of thedata display control apparatus in the first to sixth embodiments (shownin the flowcharts in FIGS. 14, 20, 23, 25, 28, and 32) and theprocessing of the data display control information editing apparatuses10000 and 10500 in the seventh and eighth embodiments (shown in theflowcharts in FIGS. 35 and 38) may be achieved by computer programswritten in machine language, with recording media storing these programsbeing distributed and sold. These recording media can be IC cards,optical discs, floppy discs, ROMs, or other media, with the machinelanguage program recorded on the media being installed into standardhardware. This standard hardware can be a conventional personal computerwhich executes the installed machine language program, thereby realizingthe data display control apparatus of any of the first to sixthembodiments or the data display control information editing apparatus ofthe seventh or eighth embodiments.

[0470] Although the present invention has been fully described by way ofexamples with reference to accompanying drawings, it is to be noted thatvarious changes and modifications will be apparent to those skilled inthe art. Therefore, unless such changes and modifications depart fromthe scope of the present invention, they should be construed as beingincluded therein.

What is claimed is:
 1. A data display control apparatus for receiving aplurality of sets of multimedia data and a set of time controlinformation, and for controlling the display of the sets of multimediadata, the plurality of sets of multimedia data composing a plurality ofcontents which make up a broadcast program, and the set of time controlinformation being used for controlling a display of the sets ofmultimedia data, the data display control apparatus comprising: datastorage means; receiving means for extracting at least one set ofmultimedia data and the set of time control information from datatransmitted from a broadcast program transmission apparatus and storingthe received sets of multimedia data and the set of time controlinformation into the data storage means; current time informationobtaining means for obtaining a set of current time informationincluding an expression of a current time; time information judgingmeans for judging whether control relating to a display of the sets ofmultimedia data is possible by comparing the set of current timeinformation with the set of time control information; and displaycontrol means for controlling the display of the sets of multimedia databased on a judging result of the time information judging means.
 2. Thedata display control apparatus of claim 1 , wherein the set of timecontrol information is repeatedly transmitted by the broadcast programtransmission apparatus.
 3. The data display control apparatus of claim 1, further comprising: link instruction receiving means for receiving aninstruction input by a user which specifies a new content to bedisplayed; and link instruction executing means for displaying the newcontent according to the instruction received by the link instructionreceiving means.
 4. The data display control apparatus of claim 1 ,wherein the receiving means also extracts the set of current timeinformation from the data transmitted from the broadcast programtransmission apparatus, and the current time information obtaining meansobtains the current time information from the receiving means.
 5. Thedata display control apparatus of claim 1 , wherein the data storagemeans stores a time difference value which indicates a time differencebetween the expression of the current time in the set of current timeinformation and a standard control time in the set of time controlinformation, and the control judging means refers to the time differencevalue and corrects a content of the current time information using thetime difference when comparing the set of current time information withthe set of time control information.
 6. The data display controlapparatus of claim 5 , wherein the receiving means extracts the timedifference value and the set of current time information from the datatransmitted from the broadcast program transmission apparatus andstoring the extracted time difference value in the data storage means,and the current time information obtaining means obtains the set of thecurrent time information from the receiving means.
 7. A data displaycontrol apparatus for receiving a plurality of sets of multimedia datathat compose a plurality of contents which make up a broadcast program,and for controlling a display of the sets of multimedia data, the datadisplay control apparatus comprising: data storage means; receivingmeans for extracting, from data transmitted from a broadcast programtransmission apparatus, the plurality of sets of multimedia data, atleast one instruction for executing a certain operation, and at leastone set of time control information for controlling execution of atleast one related instruction, the receiving means storing the separatedsets of multimedia data, instructions, and sets of time controlinformation into the data storage means; current time informationobtaining means for obtaining a set of current time informationincluding an expression of a current time; time information judgingmeans for judging whether execution of an arbitrary instruction ispossible by comparing the set of current time information with a set oftime control information related to the arbitrary instruction; displaycontrol means for executing the arbitrary instruction based on a judgingresult of the time information judging means; link instruction receivingmeans for receiving an instruction input by a user which specifies acontent to be displayed; and link instruction executing means fordisplaying the content according to the instruction received by the linkinstruction receiving means.
 8. The data display control apparatus ofclaim 7 , wherein the instructions are instructions that control adisplay of the sets of multimedia data.
 9. A data display controlapparatus for receiving a plurality of sets of multimedia data and aplurality of sets of time control information, and for controlling thedisplay of the sets of multimedia data, the plurality of sets ofmultimedia data composing a plurality of contents which are elements ofa broadcast program, each of the plurality of sets of time controlinformation being related to a set of multimedia data and being used forcontrolling a display of the related set of multimedia data, the datadisplay control apparatus comprising: data storage means; receivingmeans for extracting at least one set of multimedia data and at leastone set of time control information from data transmitted from abroadcast program transmission apparatus and for storing the sets ofmultimedia data and the sets of time control information into the datastorage means; current time information obtaining means for obtaining aset of current time information including an expression of a currenttime; time information judging means for judging whether controlrelating to a display of an arbitrary set of multimedia data is possibleby comparing the set of current time information with a set of timecontrol information related to the arbitrary set of multimedia data;display control means for controlling the display of the arbitrary setof multimedia data based on a judging result of the time informationjudging means; link instruction receiving means for receiving aninstruction input by a user which specifies a content to be displayed;and link instruction executing means for displaying the contentaccording to the instruction received by the link instruction receivingmeans.
 10. A data display control apparatus for receiving a plurality ofsets of multimedia data and a plurality of sets of time controlinformation and controlling display of the sets of multimedia data,wherein the plurality of sets of multimedia data compose a plurality ofcontents which make up a broadcast program, and each set of time controlinformation corresponds one of the plurality of contents, the datadisplay control apparatus comprising: data storage means; receivingmeans for extracting at least one set of multimedia data and at leastone set of time control information from data transmitted from abroadcast program transmission apparatus and storing the sets ofmultimedia data and the sets of time control information into the datastorage means; current time information obtaining means for obtaining aset of current time information including an expression of a currenttime; link instruction receiving means for receiving an instructioninput by a user which specifies a content to be displayed; linkinstruction executing means for displaying the content according to theinstruction received by the link instruction receiving means; timeinformation judging means for judging, when the link instructionexecuting means displays the content, whether control relating to adisplay of the content is possible by comparing the set of current timeinformation with a set of time control information related to thedisplayed content; and display control means for controlling the displayof the content based on a judging result of the time information judgingmeans.
 11. A data display control apparatus for receiving a plurality ofsets of multimedia data, at least one instruction, and one set of timecontrol information related to each instruction, and for controllingdisplay of the sets of multimedia data by executing the instructions,wherein the plurality of sets of multimedia data compose a plurality ofcontents which make up a broadcast program, and wherein each set of timecontrol information is used for controlling execution of the relatedinstruction, the data display control apparatus comprising: data storagemeans; receiving means for extracting at least one set of multimediadata, at least one instruction, and at least one set of time controlinformation from data transmitted from a broadcast program transmissionapparatus and storing the received sets of multimedia data, the receivedinstructions, and received sets of time control information into thedata storage means; current time information obtaining means forobtaining a set of current time information including an expression of acurrent time; time information judging means for judging whether anexecution of an arbitrary instruction is possible by comparing the setof current time information with a set of time control informationrelated to the arbitrary instruction; display control means forexecuting the arbitrary instruction based on a judging result of thetime information judging means; link instruction receiving means forreceiving an instruction input by a user which specifies a content to bedisplayed; and link instruction executing means for displaying thecontent according to the instruction received by the link instructionreceiving means.
 12. The data display control apparatus of claim 11 ,wherein the sets of time control information are also related to thecontents, and the display control means executes the arbitraryinstruction when a content related to the set of time controlinformation compared by the time information judging means is beingdisplayed.
 13. The data display control apparatus of claim 11 , whereineach set of time control information indicates an absolute control timeand the set of current time information includes an absolute currenttime as the expression of a current time, and the time informationjudging means judges that execution of the arbitrary instruction ispossible when the control time is equal to or earlier than the absolutecurrent time.
 14. The data display control apparatus of claim 11 ,wherein each set of time control information indicates a control elapsedtime and the set of current time information indicates an elapsed timefrom a start of a display of a current content as the expression of acurrent time, and the time information judging means judges thatexecution of the arbitrary instruction is possible when the elapsed timeis equal to or greater than the control elapsed time in a set of timecontrol information for the arbitrary instruction.
 15. A data displaycontrol apparatus for receiving a plurality of sets of multimedia data,at least one instruction, and at least one set of time controlinformation, and for controlling display of the sets of multimedia data,wherein the plurality of sets of multimedia data compose a plurality ofcontents which make up a broadcast program, wherein the instructions areused to control a display of the sets of multimedia data, and whereineach set of time control information is used for controlling executionof a related instruction and is also related to a grouping of sets ofmultimedia data, the data display control apparatus comprising: datastorage means; receiving means for extracting, from data transmittedfrom a broadcast program transmission apparatus, at least one set ofmultimedia data, at least one instruction, at least one set of timecontrol information, and a set of identification information for agrouping of sets of multimedia data, and for storing the sets ofmultimedia data, the received instructions, the received set of timecontrol information, and the received set of identification informationinto the data storage means; current time information obtaining meansfor obtaining a set of current time information for a current time; timeinformation judging means for judging whether execution of an arbitraryinstruction is possible by comparing the set of current time informationwith a set of time control information related to the arbitraryinstruction; display control means for referring to the received set ofidentification information, and, when a set of multimedia data belongingto the grouping of sets of multimedia data identified by the set ofidentification information is being displayed, executing the arbitraryinstruction based on a judging result of the time information judgingmeans; link instruction receiving means for receiving an instructioninput by a user which specifies a content to be displayed; and linkinstruction executing means for displaying the content according to theinstruction received by the link instruction receiving means.
 16. A datadisplay control apparatus for receiving a plurality of sets ofmultimedia data, at least one instruction, and at least one set of timecontrol information, and controlling a display of the sets of multimediadata according to an operation indication input by a user, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the instructions control a display ofthe sets of multimedia data, and each set of time control informationrelates to an execution of an instruction, the data display controlapparatus comprising: data storage means; receiving means for extractingat least one set of multimedia data, at least one instruction, and atleast one set of time control information from data transmitted from abroadcast program transmission apparatus and storing the received setsof multimedia data, the received instructions, and the received sets oftime control information into the data storage means; current timeinformation obtaining means for obtaining a set of current timeinformation for a current time; operation indication receiving means forreceiving the operation indication input by the user; time informationjudging means for judging, when the operation indication receiving meansreceives the operation indication, whether execution of an arbitraryinstruction is possible by comparing the set of time control informationrelated to the arbitrary instruction with the set of current timeinformation; and display control means for executing the arbitraryinstruction based on the judging result of the time information judgingmeans.
 17. A data transmission apparatus for transmitting a plurality ofsets of multimedia data, wherein the plurality of sets of multimediadata compose a plurality of contents which make up a broadcast program,the data transmission apparatus comprising: transmission data storagemeans for storing the plurality of sets of multimedia data and a set oftime control information used for controlling display of the pluralityof sets of multimedia data; and transmission means for transmitting theplurality of sets of multimedia data and the set of time controlinformation.
 18. The data transmission apparatus of claim 17 , whereinthe transmission means repeatedly transmits the set of time controlinformation.
 19. The data transmission apparatus of claim 17 , whereinthe transmission data storage means further stores a set of linkinformation which shows interrelations between contents in the pluralityof contents, and the transmission means also transmits the set of linkinformation.
 20. The data transmission apparatus of claim 17 furthercomprising: time measuring means for measuring a current time, whereinthe transmission means further transmits a set of current timeinformation showing the current time.
 21. The data transmissionapparatus of claim 17 , wherein the transmission data storage meansstores a time difference value which indicates a time difference betweenthe current time and a standard control time in the set of time controlinformation, and the transmission means further transmits the timedifference value.
 22. A data transmission apparatus for transmitting aplurality of sets of multimedia data, wherein the plurality of sets ofmultimedia data compose a plurality of contents which make up abroadcast program, the data transmission apparatus comprising:transmission data storage means for storing the plurality of sets ofmultimedia data, at least one instruction for executing a certainoperation, at least one set of time control information for controllingan execution of a related instruction, and a set of link informationwhich shows interrelations between contents in the plurality ofcontents; and transmission means for transmitting the plurality of setsof multimedia data, the instructions, the sets of time controlinformation, and the set of link information.
 23. The data transmissionapparatus of claim 22 , wherein each of the instructions controls adisplay of a set of multimedia data.
 24. A data transmission apparatusfor transmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatuscomprising: transmission data storage means for storing the plurality ofsets of multimedia data, a plurality of sets of time control informationthat each correspond to one set of multimedia data and are used tocontrol a display of a corresponding set of multimedia data, and a setof link information which shows interrelations between contents in theplurality of contents; and transmission means for transmitting theplurality of sets of multimedia data, the plurality of sets of timecontrol information, and the set of link information.
 25. A datatransmission apparatus for transmitting a plurality of sets ofmultimedia data, wherein the plurality of sets of multimedia datacompose a plurality of contents which make up a broadcast program, thedata transmission apparatus comprising: transmission data storage meansfor storing the plurality of sets of multimedia data, a plurality ofsets of time control information that each correspond to one content andare used to control a display of a corresponding content, and a set oflink information which shows interrelations between contents in theplurality of contents; and transmission means for transmitting theplurality of sets of multimedia data, the plurality of sets of timecontrol information, and the set of link information.
 26. A datatransmission apparatus for transmitting a plurality of sets ofmultimedia data, wherein the plurality of sets of multimedia datacompose a plurality of contents which make up a broadcast program, thedata transmission apparatus comprising: transmission data storage meansfor storing, the plurality of sets of multimedia data, at least oneinstruction for controlling display of the sets of multimedia data, atleast one set of time control information for automatically starting anexecution of a related instruction; and a set of link information whichshows interrelations between contents in the plurality of contents; andtransmission means for transmitting the plurality of sets of multimediadata, the instructions, the sets of time control information, and theset of link information.
 27. The data transmission apparatus of claim 26, wherein each set of time control information indicates a control timewhich is an indicated time.
 28. The data transmission apparatus of claim26 , wherein each set of time control information indicates a controlelapsed time showing an elapsed time from a start of display of apredetermined content.
 29. A data transmission apparatus fortransmitting a plurality of sets of multimedia data, wherein theplurality of sets of multimedia data compose a plurality of contentswhich make up a broadcast program, the data transmission apparatuscomprising: transmission data storage means for storing the plurality ofsets of multimedia data, at least one instruction for controlling adisplay of the sets of multimedia data, at least one set of time controlinformation, and a set of link information which shows interrelationsbetween contents in the plurality of contents, wherein each set of timecontrol information is composed of time information for an automaticstart of execution of one of the instructions and is related to agrouping of sets of multimedia data; and transmission means fortransmitting the plurality of sets of multimedia data, the instructions,the sets of time information, and the set of link information.
 30. Adata transmission apparatus for transmitting a plurality of sets ofmultimedia data, wherein the plurality of sets of multimedia datacompose a plurality of contents which make up a broadcast program, thedata transmission apparatus comprising: transmission data storage meansfor storing the plurality of sets of multimedia data, at least oneinstruction for controlling a display of the sets of multimedia data, atleast one set of time control information which is used as a criterionby a reception apparatus in judging whether to execute a relatedinstruction; and a set of link information which shows interrelationsbetween contents in the plurality of contents; and transmission meansfor transmitting the plurality of sets of multimedia data, theinstructions, the sets of time control information, and the set of linkinformation.
 31. A data display control information editing apparatusfor displaying interrelations between a plurality of contents on adisplay screen and for editing, in accordance with a user operation,sets of time-related information that are used for controlling theinterrelations, the data display control information editing apparatuscomprising: data storage means for storing a plurality of pairings of aset of link information and a set of valid period information andstoring a set of content control information, wherein each set of linkinformation indicates a change in display from a first content to asecond content, each set of valid period information indicates a validperiod of a corresponding set of link information, and the set ofcontent control information is used for controlling display andprocessing of contents; time receiving means for receiving an indicatedtime input by a user; and content relation displaying means fordisplaying interrelations between contents at the indicated timereceived by the time receiving means, based on the pairings of a set oflink information and a set of valid period information which has a validperiod that includes the indicated time received by the time receivingmeans.
 32. The data display control information editing apparatus ofclaim 31 , further comprising: content specification receiving means forreceiving a specification of a content input by a user; and linkinformation updating means for updating a set of valid periodinformation of a set of link information which indicates a change indisplay to the content specified by the user so that the set of linkinformation is made invalid at the indicated time received by the timereceiving means.
 33. The data display control information editingapparatus of claim 32 , wherein the sets of link information and thesets of valid period information are transmitted from a transmissionapparatus used in a digital broadcast system to a data display controlapparatus which displays contents.
 34. A recording medium on which adata display control program is recorded, the data display controlprogram controlling a data display control apparatus which receives aplurality of sets of multimedia data and a set of time information andcontrols display of the sets of multimedia data using the set of timecontrol information, wherein the plurality of sets of multimedia datacompose a plurality of contents which make up a broadcast program, thedata display control program comprising the steps of: obtaining a set ofcurrent time information for a current time; judging whether controlshould be performed by the data display control apparatus to display thesets of multimedia data by comparing the set of current time informationwith the set of time control information; and having the data displaycontrol apparatus control a display of the sets of multimedia data basedon a judging result of the judging step.
 35. A recording medium on whicha data display control program is recorded, the data display controlprogram controlling a data display control apparatus which receives aplurality of sets of multimedia data, at least one instruction, and atleast one set of time control information related to each instruction,and controls a display of the sets of multimedia data using theinstructions, the plurality of sets of multimedia data composing aplurality of contents which make up a broadcast program, and each set oftime control information being used for controlling an execution of therelated instruction, the data display control program comprising thesteps of: obtaining a set of current time information for a currenttime; judging whether an arbitrary instruction should be executed by thedata display control apparatus by comparing the set of current timeinformation with a set of time control information related to thearbitrary instruction; having the arbitrary instruction executed by thedata display control apparatus based on a judging result of the judgingstep.
 36. A recording medium on which a data display control informationediting program is recorded, the data display control informationediting program controlling a data display control information editingapparatus which displays interrelations between contents on a displayscreen and edits a set of time information used for controlling theinterrelations, the data display control information editing programcomprising the steps of: instructing the data display controlinformation editing apparatus to receive an input of an indicated timefrom a user; and referring to content control information forcontrolling a display of a content and execution of a predeterminedprocess and to sets of link information that each indicate a switchingof display from a first content to a second content, and instructing thedata display control information editing apparatus to displayinterrelations between pairs of contents on the display screen at theindicated time, based on the sets of link information that are valid atthe indicated time.